This is, first of all, a summary of how githyanki society has fractured post-Vlaakith, as it has evolved in my BoG'r campaign. Comments, additions, ideas, and criticisms are VERY welcome.
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The Ascendancy (also known individually as 'Loyalists') are seeking a new queen. They have the unquestioning support of the knighthood and many warbands, but there are three competing candidates. Collectively they are known as the Princesses of The Ascendancy, and all are powerful sorceresses like the former Vlaakiths.
-'The White Lady' is a lich with the support of the 'Court of Vlaakith', the Lich Queen's former victims, now undead residing on the Neg-energy plane. She also has support from many knights, and some even claim she IS the former Vlaakith, who has regenerated a new body. Such a thing, they say, has happened before, specificly Vlaakiths CLI through CLVII.
-'The Young Heir' is supported primarily by the knighthood, some of whom claim she is indeed the genetic heir of the royal line (and who would know better?). However, an equal number of knights claim that the royal line was wiped out at the behest of Vlaakith CLVII, and that her claim is therefore false. Her supporters claim that one of the knights so tasked had saved a single royal egg. The official line is that this was so ordered by Vlaakith, but rumors abound that the knight had actually comitted treason in saving her.
-'The Singer of Fire' is a half-dragon. She has the least support among githyanki, but she has ties to the Cult of Tiamat, the only Githyanki still benefiting from the Dragon Alliance. A few knights support her, as she too claims to be of the line of Vlaakith. She has the least support for her bid amoung githyanki, so she has cast her net wider than the others, contacting githyanki exiles and emissaries and promising a place in the new order in return for their material support.
The Heartforce is made up of several powerful Governors-Millitant and warband leaders in the largest Astral cities and fortresses. They reject The Ascendancy, claiming that the destruction of Vlaakith has ushered in a new era for the People. They are a cautious and pragmatic group, distrusting each other almost as much as they distrust other blocs. They have been known to react harshly towards individuals trying to drum up support for other power blocs in their cities. Their power is due to many loyal warriors and to their control of many portals and color-pools.
The Silver Eyes are seekers across the planes. They look for magic and psionic items to use against the Illithid. They collect intelligence and train infiltrators. They reseach lost and forbidden knowledge in their quest to bring down the illithid threat once and for all. Some seek for signs of the return of Gith herself. Others seek her regalia: The Sword of Gith, Gith's Tiara, and The Dagger of Gith. Few openly oppose them in their goals, and they have, perhaps, the best relations with other power blocs.
The Cult of Tiamat are half-dragons and supporters. They are the only Githyanki for whom the Dragon Alliance still holds. A very few have begun to wield priestly powers. They are a slippery group, supporting a Princess of the Acendancy, yet at the same time having close ties to The True. They are more concerned with their own grab for power than with the wars against the Githzerai and the Illithid.
The True believe that Gith's soul has returned, and resides in a young Gish known as Ar-Gish, "the great Gish". Her original Warband are loyal believers, as many were there on the battlefield when they say it happened, and Gith's soul entered into her. They do not support the Acendancy, yet are very close to the Cult of Tiamat. They are fervent belivers in The War of Two Skies, battling against their long-sundered kin, the Githzerai.
The Reconciliation opposes the continuation of The War of Two Skies. They consist of the most fanatic Illithid-hunters and Silver Eyes who believe in the wake of the Lich Queen's demise the mind flayers will gain power. They have little support in the Astral, since rumors linked them to Vlaakith CLVII's death. However, they do have a resource no other group has in their counterparts among the Githzerai.
The Unifists believe that githyanki society, though fractured, will re-unite and become stonger for the current troubles. Ironicly, they are the least organized. There are many within other power blocs who are sympathetic to the Unifists' goals, but who believe their own bloc stands the best chance of unifying the githyanki by coming out on top. The Unifists may have much ideological support among rank-and-file githyanki, but they tend to act individually. Their efforts tend to be disjointed, grass-roots affairs. Their biggest problem is that they have trouble keeping their mouths shut, putting them at odds with the Heartforce. Vocal Unifists tend to disappear rather quickly from the streets of the Heartforce's cities and forts.
The Apocalytes are reminants of the Lich Queen's Incursion armies on several prime plane worlds, who have refused to flee back to the Astral. Many have embraced a nihlistic perspective and seek their own deaths in battle, though still hoping to deal the illithid and the graith as serious of wounds as they can in their final days and hours. At the other end of the spectrum, some of the more stable Incursion Empires have rejected the traditional xenophobia of the githyanki and court allies amoung the barbarians.
Githyanki Power Blocs
Zimrazim brought up some interesting points in a PM to me in response to this thred. I will attempt to illuminate my take on some of this, but as always others' ideas are welcome.
I really don't think the Lich Queen's ultimate plans would be well known. Those few who were privy to all this are probably either destroyed along with her or guilty themselves, and so wisely mum on the whole "githyanki genocide" plan.
It would certainly be interesting, however, for this to crop up in-game, as either the Reconciliation tries to obtain then protect someone who could testify to this, or someone else "learns the truth".
Ah, yes! Hence why the most powerful of Supreme Leaders have banded together to oppose the Ascendancy of a new queen, forming the Heartforce.
The Reconciliation: While the Sha'sal Khou form the original core of this power bloc, the majority of its current members are likely made up of those who 'merely' oppose the War of Two Skies for various reasons but never plotted against the Queen. Those people and groups (Band of Iron?) who came to oppose the Two Skies on their own are likely being actively courted by Zetch'r'r's supporters. Zetch'r'r may also have his eye on other very high-level githyanki who aren't eager to see a return to the ritual of retirement.
It's worth noting that the illithid likely hate the Reconciliation, bad, because the prospect of the githyanki and githzerai united against them absolutely terrifies them.
I happen to like the "What happened to Zetch'r'r?" mystery. Did he die along with the Lich Queen? Was he assassinated shortly thereafter? Or did he just decide to disappear for awhile? Actually, in terms of BoG'r, I haven't decided yet, but like I said, I like the mystery aspect.
The Reconciliation, as it exists post-Vlaakith, is not exactly the same as the Sha'sal Khou from Incursion. The Sha'sal Khou may have even officially disbanded with the Lich-Queen's destruction, to cover their tracks. The Reconciliation is both larger and less organized than the Sha'sal Khou were, but not by much, really. For instance, the entire Band of Iron isn't considered to be in the Reconciliation bloc, but many individual members might be.
The Reconciliation might have some allies among the Heartforce. Even if the local Supreme Leader is not sympathetic to peace with the Zerth, other power blocs are banned from the Heartforce's fortresses, but the former Sha'sal Khou are much more used to operating in secret than any other githyanki.
The Reconciliation is politicly closest with the Silver Eyes, who tend to consider the illithid threat the most important, and the War of Two Skies as secondary.
Backstory that hasn't come up in-game but may: The True reject the Ascendancy. Some of the True even claim that Vlaakith I betrayed Gith, and the whole line of queens are usurpers! Strangely though, they have good relations to the Cult of Tiamat (though they reject the Singer of Fire's claim to Vlaakith's throne), hinting that the Dragon Alliance was Gith's doing, not Vlaakith's.
The True are also the most fanatic foes of the Reconcilliation. To them the War of Two Skies can only end with the total destruction of all githzerai, and Zerthimon's teachings along with them.
Neat ideas with many seeds. I figure of all the githyanki, it is the knights who are the most lost without Vlaakith. 80-90% have jumped aboard with the Ascendancy, basicly because they have no idea what else to do except find another Queen. The fact that there are three Princesses fractures them even further. Basicly, the kights are broken as an organization, but most githyanki still fear/respect them individually.
I don't see a huge increase in "Power Slaves" as githyanki society considers priests, though since they started at nearly zero, any increase will be significant. Githyanki society and tradition is at least as reponsible for the low number of priests as Vlaakith's knights hunting down heretics were. Priests serving a power will still be considered heretics by their brothers, I don't see this changing very quickly. There are, however, a few exceptions:
- Wielders of divine magic who don't serve a particular Power, but rather an aspect, especially one that githyanki tend to be comfortable with, like "liberation".
- Priests of Tiamat. These are in fact one of the Cult of Tiamat's aces in the hole, duthka'gith and even some githyanki who now wield priestly powers in the Queen of Evil Dragons' name.
- Priests of dead Powers from the Astral. While there are probably ony a few more of these popping up than before, the mechanism for hunting them down and putting them to the (silver) sword has broken down, so quite a few more will be appearing on the scene.
Note that these examples do not include priests of other humanoid Powers. The githyanki mindset would not easily accept serving a "barbarian diety", so even if a priest of, say, Wee Jas, were to arise (in itself doubtful), she would be rejected by githyanki society.
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Note that my comments, though sometimes conradictory, are not meant to reject or dismiss Zim's ideas. That is to say, I love the feedback, and will take it all under advisement.
As should any lurkers wanting to run their own githyanki campaigns. 
The Unifists are a new addition, aren't they? I'm guessing that's where you wanted to have Gy-Nath at... and they also seem like they would appeal to Du'minh (though he would hope the People would reunite despite current order of day, not because of it).
I'd suggest adding a quirk or two to them, since they might come off as a bit bland (if you don't mind me saying so).
Yes indeed, the Unifists were made to basicly include the philosophies of Gy-Nath and Du'minh. As for them being a bit bland, well I certainly don't want that 
. That's why I made them "ironicly, the least organized". I figure that there are alot of githyanki within other power blocs who are working toward the reunufication of the empire, its just that they believe this will best be accomplished by, say, revival of the Dragon Alliance once The Singer of Fire becomes Queen, or the illithid are dealt a crushing blow, or all githyanki accept "Gith-reborn" and join The True.
Basicly, few reject the notion that the githyanki people should come back together, but nobody can agree as to the MEANS. Then you have guys like Gy running around, trying to show githyanki they can still work together towards a cause greater than their political squables, alternately believing their grass-roots efforts will be the salvation of the People and then getting hit by setbacks.
Of course, if you think of some more quirks to keep 'em interesting ...
The True are also the most fanatic foes of the Reconcilliation. To them the War of Two Skies can only end with the total destruction of all githzerai, and Zerthimon's teachings along with them.
If they wish to, the True might have some luck gaining allies among the Gith pirates, at least according to this: http://www.spelljammer.org/monsters/conversions/PirateOfGith.html
I figure that those pirates who have any interest in githyanki politics would lean toward True (mostly) or Cult of Tiamat (a minority).
It hasn't come up in-game, but I think that an "ideal" future, in Ya'shenn's opinion, would actually not involve the return of a monolithic and probably repressive empire. She wouldn't want the People to exist in a state of continual civil war, of course, and she would want them to be able to unite against external threats (illithid), but she would like to see a future where two Githyanki can materially disagree without either of them feeling obligated to slay the other.
In the extreme long-term, she might even see a fracturing and a diaspora as desirable. (Consider the githzerai -- illithids on the Planes seem to consider them overall a more dire threat, since they're so much more widespread all over the planes.) She has a number of inflammatory ideas, though.
I like! Summary above modified.
EDIT: New group added
. That's why I made them "ironicly, the least organized". I figure that there are alot of githyanki within other power blocs who are working toward the reunufication of the empire, its just that they believe this will best be accomplished by, say, revival of the Dragon Alliance once The Singer of Fire becomes Queen, or the illithid are dealt a crushing blow, or all githyanki accept "Gith-reborn" and join The True.
Basicly, few reject the notion that the githyanki people should come back together, but nobody can agree as to the MEANS. Then you have guys like Gy running around, trying to show githyanki they can still work together towards a cause greater than their political squables, alternately believing their grass-roots efforts will be the salvation of the People and then getting hit by setbacks.
Of course, if you think of some more quirks to keep 'em interesting ...Another major form of opposition to the Unifists might also come from the divisive beliefs that are fairly common throughout Githyanki society, and in the specific factions themselves. For example, a Unifist might (grudgingly) tolerate a githyanki who worships a barbarian deity, while most Githyanki (orthodox or otherwise) would find such heathen beliefs disgusting. Many githyanki dislike duthka'giths -- most out of pure xenophobia, others for ideological reasons. A Unifist might be more tolerant of a gith pirate or Athasian gith, while most Githyanki don't think much of either. Basically, even nonconformist githyanki (such as many of Git'riban's inhabitants) still have plenty of hate to go around.
Reviving this post.
I'm thinking of doing some articles on the Power Blocs {I like this term, it is sufficiently different from "factions" and has a good githyanki ring to it} for the Rrakkma section. I'd like as much of anybody's input as they want to give, to flesh out the Blocs some more.
The first article will be "The True"
I just got a look at that - looks nice and tight (though my spellchecker tried to choke a few times) - it's in the queue and up to get published next week. Have you thought about symbols for these groups that could be used to illustrate the articles?
Submitted two more blocs, The Apocalytes and the Silver Eyes. I'm also working on the Unifists and beginning to get smatterings of ideas for the Ascendancy and the Heartforce. I'd like some help with more ideas about how to make these groups more interesting, if anyone has them. I feel a little odd developing certain power blocs without input from older Rrrakkma project members. The Apocalytes are my invention, but I can't take credit for the Heartforce. Anyway, I'll go back and read earlier development threds, and try to incorporate the ideas expressed, which'll be kind of like getting contributer.
As for symbols, I've a few ideas, but somebody else should do the art.
The True - A sword with a light blue halo of light.
The Silver Eyes - A pair of silver eyes or a dagger on a tome with said eyes.
The Apocalytes - A flaming sword or an illithid skull
The Unifists - Three interlaced circles
The Ascendancy - A crown
The Cult of Tiamat - A flame or a dragon's scale
The Reconciliation - A handle with dagger blades on either end
The Heartforce - A tower
Any colorful Heartforce NPCs (most likely supreme leaders) you could use as examples? Does the Heartforce have a single leader (or small group of leaders) at this point, or are they highly fragmented? Can they agree on anything (other than a general dislike of the Ritual of Retirement)?
I'm guessing that among Heartforce rank-and-file, the biggest reason most of them are in the Heartforce is due to deep personal loyalty to their own warband commanders, rather than adherence to one of the other philosophies/religious ideals available.
A few notes on names for those who want to be in the know:
The Heartforce is a name I did not come up with, but which I like very much.
The Apocalytes derive their name from "Alcolytes" and "Apocalypse"
The Unifists have the word "fist" in their name because they are githyanki and therefore no less violent than any others, and because the easiest way to get githyanki to work together is to get them killing other races they don't like (like illithids or githzerai)
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I have also put some thought into alternate nicknames for the power blocs that may be used in conversations between githyanki.
The Ascendancy: Loyalists (a positive term), Followers (a less-than-positive term), Deluded Fools (way negative term)
The Heartforce: Defenders (pos), Opportunists (neg)
The Reconcilliation: Zerth-lovers (neg)
Apocalytes: Dead-enders (neg), The Hopeless (neg)
Unifists: Binders (pos), Rabble-rousers (neg)
The Silver Eyes: Watchers (pos), Manipulators (neg)
The Cult of Tiamat: Heretics (neg)
I'm guessing that among Heartforce rank-and-file, the biggest reason most of them are in the Heartforce is due to deep personal loyalty to their own warband commanders, rather than adherence to one of the other philosophies/religious ideals available.
I concur with the last point and think that a likely indication that there is no single recognized leader of the Heartforce. These are pretty dramatically turbulent times, so Heartforce members are probably generally those prone to cling to the immediate loyalties of their captains and warband commanders rather than distant generals that issue orders from Astral fortresses far removed from their own, even though the latter may also be Heartforce members.
Sorry, will try to think of some more solid input. Any particular blocs or aspects of blocs you want more help developing?
As to the Heartforce, I would emphasize that their holdings generally can be found among the established Astral fortresses that lie distant from Tunarath. There are likely significantly reinforced fortresses located near well-travelled Astral portal-clusters or color pools, even though they are on the fringes of gith-controlled territory. Many of these probably has their share of contact with outsiders who come to trade or negotiate safe passage, and thus they are in a position to be exposed to many foreign ideas and beliefs which go contrary to a strongly centralized empire.
I can also imagine that prominent warbands would include those who have experienced a glorious powerful commander being devoured by Vlaakith. Though many loyalists probably sees it as an honor, there will surely be soldiers who served under the commander that see it more like a betrayal in spite of their service to the empire.
The Heartforce: Defenders (pos), Opportunists (neg)
The Reconcilliation: Zerth-lovers (neg)
Apocalytes: Dead-enders (neg), The Hopeless (neg)
Unifists: Binders (pos), Rabble-rousers (neg)
The Silver Eyes: Watchers (pos), Manipulators (neg)
The Cult of Tiamat: Heretics (neg)
Apocalytes: The Cornered (neg), The Lost (neg).
The Silver Eyes: The Seekers (pos).
The Cult of Tiamat: The Dragon-pawns (neg).
I like this. You could even have a famous supreme leader or two that were literally on their way to Tu'narath to be "retired" when the Empire fell apart. (Can you imagine the astonishment when said Supreme Leader returns home to his/her troops?)
Unifists will be coming soon. Next I think I'll do the Ascendacy, because I hve a few ideas concerning the the three princesses;
The Singer of Fire is the most powerful of the three, and was Tiamat's secret ace in the hole over Vlaakith.
The White Lady is second in personal power, and a very close second in popular support. Many of her followers are free-willed undead.
The Young Heir is just that, very very young, an infant in fact, who is being trained in a secret location. by advisors and regents.
Any more ideas?
Well, if the Young Heir is an infant, not much chance of her being able to interact much with PCs.
Also, I hope that there's a githyanki faction somewhere that deeply opposes the establishment of a new Queen. 
Regardless of personal power of the candidates, I would play the competition between the three groups as close to a stalemate, unless its a plot point you want to come to fruition soon. Isn't the Silver Eyes secretly doing something like that, anyway?
I remember having seen a good movie when I was younger about a period where China's emperor was a child, that would probably be a good source of inspiration for the Young Heir. Think it focused around the Forbidden City or some such. Oh yeah, and there's Indiana Jones 2 where its a kid ruling that Indian palace.
Well, if the Young Heir is an infant, not much chance of her being able to interact much with PCs.
But the same might not hold true for the old top advisor manipu-... I mean, advising the infant. 
The Heartforce seem to fill that role perfectly, and I can't imagine the Reconciliation favoring any of the candidates either (they all support the War of Two Skies, right?). I'm sure there are plenty of likeminded individuals among other factions as well...
The Heartfoce, The True, The Apocalytes, and The Reconciliation all reject the Ascendancy. The Unifists sort of do too, in that those that support a new queen join the Ascendancy instead of remaining true Unifists, but they don't generally oppose the Ascendancy openly like the others.
So, my idea is this (comments please) The Ascendancy could easily split into three opposing groups, and in a way they have, but this weakens the bloc overall. So, the three princesses have agreed (or their advisors agreed in the case of the Young Heir) to put aside (most of) their infighting and unite as a power bloc. Doing this makes them the single most powerful bloc, though one that has daggers for the backs of their other sub-blocs. Both the Singer of Fire and the White Lady have agreed to let the Young Heir go through the training and trials of a githyanki before having a shot at the throne (training which she might not survive, which would be a shame, I'm sure). This puts the battle for the ascendancy off for about 20 years. Or rather, this gives them 20 years to grow their personal and political power, assassinate rivals and perhaps each other, and convince the 'traitors' of githyanki society (which is over 50% of the population) to support them.
Sounds pretty good to me!
I would put the alliance as barely being able to hold up to the standards of a cease fire, with each side continously plotting intrigue, assassination and political power play at just about every possible turn. Each side will likely have (or try to place) spies in each others' courts and feeded misinfortation would be rife.
I have a write-up of the Ascendancy done. That leaves the Heartforce and the Reconciliation. I think that the heartforce, in particular, deserves some actual personalities associated with it. There should be one or two for every major githyanki city.
T'n'ekris, Xamvadi'm, Githmir, what are some others?
T'n'ekris, Xamvadi'm, Githmir, what are some others?
I think those are the only ones mentioned in A Guide to the Astral Plane, though I think other large cities might exist. (The majority of the total githyanki population, however, don't live in large cities.)
A note on 2e vs 3e and population:
Xamvadi'm and T'n'ekris are described in A Guide to the Astral Plane as "well-known, populated githyanki cities," but only contain 8,000 githyanki apiece! (2e)
Tu'narath had a population of 100,000 in Dungeon #100. (3e)
A population figure for Githmir isn't given in the 2e text, but I would guess it to be greater than Xamvadi'm or T'n'ekris, but less than Tu'narath. (Maybe 25,000-75,000?)
Given Githmir's status as the githyanki trade city (complete with non-githyanki residents), the NPC in charge of the place is likely to be highly interested in keeping trade going. (You know, given how cosmopolitan Githmir is, if I were the Revered Queen I might make sure that all the knights posted there are non-local... perhaps when the Queen disappeared, said knights went nuts and started slaughtering Githmir's barbarian traders and visiting adventurers wholesale!) Given the historical relationship between T'n'ekris and Xamvadi'm, those NPCs may well dislike each other (or pretend to). It would be amusing and ironic, actually, if the supreme leaders of those two cities disparaged each other in public, only to be allies of a sort in actuality... (One could easily make a joke that if the leaders of those two cities are working together, it must be a sure sign of the githyanki version of the end times.)
Xamvadi'm, T'n'ekris, and Githmir are all big enough that they might have more than one warband apiece.
Gad'idine has about 1,000 residents (Guide again), who interestingly "declared themselves outcasts from their own society." I don't know if they'd be big enough to be included in the Heartforce, but a bunch of githyanki outcasts (on the Astral, no less) who decided to make a city on the Living Sea sound like an interesting bunch.
Well, the next project will be the Heartforce, leaving the Reconcilliation for last. As I said before, I think that unlike the other Blocs, the Heartforce should be defined by a few well-known leaders. I'll take any suggestions/ideas from the gallery. I'm thinking between 1 and 3 for each of the major cities mentioned above, a couple of new made-up cities, and the commanders of a few major warbands. I'm kind of thinking up to a dozen NPCs, but this may be too many. Nine might be a better (and more significant, being 3x3) number.
As for the warbands, I'll choose a few who haven't been mentioned in the other blocs nor chosen by a PC ... I forgot which band Ya'shenn, Ar'dru, and Ii'jyka'vaar are from, but I do remember the others (Du'minh=Steel (likely a very large band), Jhank'kor=Onyx, Kirath=Copper, Na'rai=Jade, NPCs; K'tch=Pyrite, Gy-Nath=Iron, Lahar=Bloodstone, Telas-Niah=Bronze)
Possibilities for core of Heartforce: Bands of - Shale, -Slate, -Basalt, -Silver, -Gold, -Platinum, -Limestone, -Gneiss, -Emerald, -Saphire, -Feldspar, -Mica, -Olivine, -Quartz, -Amethyst, -Ruby, -Obsidian, -Cobalt, -Titanium, -Brass, -Beryl, -Agate, -Apatite, -Chalcedony, -Carnelian, -Turquoise, -Amber (wait, was Ya'shenn band of Amber??), -Flint, -Jasper, -Ivory (would this count, since it has an organic origin??), -Jet, -Malachite, -Moonstone, -Marble, -Opal, -Peridot, -Citrine, -Rutile, -Sard, -Spinel, -Topaz, -Tourmaline, -Zircon, -Amphibole ....
The other idea I have for the Heartforce is to make one of their major support groups the varsh-caste. This would make sense in their chosen name.
Amber, though having been based on Tu'narath, her warband is very nearly extinct.
Amber is of organic origin, though I don't know if the githyanki would realize that amber is fossilized tree resin.
I think titanium might be anachronistic for the setting (see the wiki article on what a pain it is to get titanium from ores). Platinum might work, but its melting point is very high.
Actually, here's an idea -- I can imagine Githmir, as the trade city, may be stereotyped as the most materialistic of githyanki cities (so they prefer the most valuable stones/metals for their warbands). The melting point of platinum is so high (over 3200 degrees F) that you'd probably need either mages or duthka'giths to smelt the stuff. Perhaps there is a Band of Platinum that is known for its mages, duthka'giths, or both. They may also be associated with mining interests on the Prime Material Plane and definitely with metals smelting. (Say, do githyanki have their own mint for coins? Platinum pieces aren't easy to smelt.)
If Gad'idine is included, their warband(s) may be named after blue, green, or blue-green stones, or a stone that comes from the sea (pearls)?
The other idea I have for the Heartforce is to make one of their major support groups the varsh-caste. This would make sense in their chosen name.
Wouldn't most of the big blocs also still have varsh for training their young, though? Its sort of a central thing in the overall structure of gith society, so I'd imagine at least the Ascendancy also has their share of varsh and facilities for the young.
Perhaps the varsh, more than some castes, simply tend to adhere strongly to their individual warbands. Many of them would support the Heartforce for this reason, but if their warband strongly leans toward another faction, the varsh of that warband might as well.
Amber is of organic origin, though I don't know if the githyanki would realize that amber is fossilized tree resin.
I think titanium might be anachronistic for the setting (see the wiki article on what a pain it is to get titanium from ores). Platinum might work, but its melting point is very high.
If Gad'idine is included, their warband(s) may be named after blue, green, or blue-green stones, or a stone that comes from the sea (pearls)?
Yes, I think that they'd know the origin of Amber, as well as Pearl and Ivory. All 3 are warbands then, but not Coral, or Fossil, though. There's a kind of wood that only comes from burried trees subject to partial fosilization, but I don't remember the name. I'd use the "does it sond cool?" test as to whether I'd use it.
Yea, not titanium, but Platinum, Tin (another one I forgot), and perhaps exotic magical metals (though I personally frown on these, there are plenty of mundane gemstones and metals without a PC insisting he's from the band of mithril.)
Gad'idine is the band of Pearl then. Should they be included in the Heartforce?
The Heartforce should be held together by warband loyalty. I'm playing with the idea of not acually giving the Heartforce leaders actual names as NPCs, but instead referring to them in terms of rank, title, and warband affiliation.
The warband names I'd like to use are some of the likely large (common gemstones like quartz) or contain large mlar castes (the utilitarian stones and metals like Marble, Granite, and Tin).
Maybe Marble as one of the Githmir warbands, as it's one of the more valuable of the "utilitarian" stones. A Band of Quartz might be associated with psionics.
S0,
Gad'idine = Band of Pearl and elements of the Band of Saphire
Githmir = Band of Gold, Band of Platinum (small, mostly mlar-caste), Band of Marble.
Xamvadi'm & T'n'ekris = {should be contrasting, maybe Gold, Ruby, and Garnet vs. Silver, Diamond, and Moonstone. Other ideas?}
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Major Warband Holdings
The Bronze Tower
Ironrock
The Bloodstone Tiers
{these 3 were background areas I already had for Incursion and my NPCs for BoG'r (some of whom, by the way, are NPCs from Incursion and my home PS game). I prefer "translated" names rather than making up a githyanki-sounding word for holdings of a single warband, while multi-warband cities have githy names}
The Pillars of Basalt, Slab
The Granite Armory
The Marble Halls
The Brass Bell (the remains of a dead god of protection)
The Silver City
The Diamond Shard
{large warbands should be very common elements, and I agree that gemstone names should determine the character of the band.}
LARGE BANDS
Quartz - Psi focus. Most githwarriors are actualy giph (psi-warriors or psion/fighters) & they train many psions.
Copper, Brass, & Bronze - Large and diverse, with many sub-bands
Silver - One of the largest bands, many sub-bands, mages, some specialists in Astral travel and lore.
Marble - mlar-heavy band represented in several cities
Ruby - sorcery and Gish-caste
Garnet - large but typical, many githwarriors and fighters with some sorcers, psions, Gish-caste, mlar-cast, etc.
Iron & Steel - Large and warrior-heavy
Flint, Slate, Limestone, and Granite - mlar-heavy
Basalt - Mlar-heavy but also known for warlocks, necromancers, and heavy shock-troops
medium bands
Jade - psions, psi-warrios, Gish, mages
Amethyst - Psions
Emerald - Saphire - Feldspar - Obsidian - Agate -Turquoise - Amber - Jasper - Ivory - Jet - Moonstone - Opal - Topaz - Zircon - Onyx
small warbands
Chalcedony - Mica - Platinum - Beryl - Apatite - Carnelian - Malachite - Peridot - Citrine - Rutile - Sard - Spinel - Tourmaline - Diamond
********
Below the warband level, there are many academies, orders of knights, training centers for various castes, etc. Some of therse are affiliated with a particular warband, but a equal number are not. Sometimes a recruit goes back to her own warband, sometimes not.
Varsh'isks may be held by a single warband, or may be joint holdings. Traditionally, Varsh'isks often swap clutches of eggs to mix the gene-pool.
Band of Ivory -- Perhaps this warband is more focused on Prime Material Plane operations than most. As such, it may have more rangers, scouts, etc., than most bands. If anyone is in contact with the Apocalytes (and quite possibly members of the power bloc) it would be this warband.
Band of Platinum -- The Band of Platinum has enough material wealth to buy and sell several other warbands, though among the githyanki this means somewhat less than it might among graith. Heavily involved in the metals, mining, and metalworking trades, they are more involved in the production of Astral godsteel than many warbands, and their mlar produce the githyanki currency. The varsh of this small and unusually insular warband do not normally exchange eggs with other warbands, and are picky about adopting outsiders into the warband. The Band of Platinum is mlar-heavy and those of the martial caste are often mages (especially fire-elementalists) or gish. While this warband is known for its magical talents, they are not especially known for psi, and psions (or giph) in the warband are likely to be pyrokineticists or have other talents related to metalworking. The duthka'giths of Platinum are better integrated than most, and are often chosen for adoption into the band.
Possibly due to the fact that they don't exchange eggs with other warbands, a large number of Platinum githyanki have hair that prematurely turns gray, silvery-gray, or white. Generally, the githyanki of Platinum are known to be a conservative lot. The aging commander of Platinum is believed to have been quite close to 'retirement' age (and probably past it now...), and maintains at least some dialogue with the Ascendancy, though he has not yet spoken out strongly in favor of any of the three candidates.
Band of Turquoise -- The Band of Turquoise does much to perpetuate the stereotype of the githyanki of Githmir as being greedy, materialistic, and overly liberal. Somewhat younger, and much larger, than the Band of Platinum, the Turquoises regularly exchange eggs with other warbands and both adopt new members (and allow them to join other warbands) rather easily. They are known for being willing to buy or sell virtually anything, and will trade with almost any sort of graith as long as it doesn't have tentacles. Most of its members have a greater understanding of non-githyanki cultures than typical githyanki, and many are multilinguistic as well. The Band of Turquoise produces githwarriors, mages, psions, gish, giph, and so on in fairly equal numbers, though they produce rather fewer knights, and more bards, than many warbands. This warband has produced a number of well-known playwrights, and some famous playwrights have been adopted into the band. The current commander of Turquoise is particularly interested in keeping trade flowing (since anarchy is bad for business) but is unlikely to strongly favor the Ascendancy. The Band of Turquoise has ties with Gith pirates and a variety of other non-githyanki entities on other planes.
I need a little help here. I have 2 more power blocs to go, but hit writers block instead.
I'll try to come up with some ideas and get back to you.
Though there's no need to stress; we'd rather our great DM doesn't burn himself out. 
Jade - psions, psi-warrios, Gish, mages
Amethyst - Psions
Emerald - Saphire - Feldspar - Obsidian - Agate -Turquoise - Amber - Jasper - Ivory - Jet - Moonstone - Opal - Topaz - Zircon - Onyx
Was this up before I wrote my background? If so I feel very stupid.
Jade - psions, psi-warrios, Gish, mages
Amethyst - Psions
Emerald - Saphire - Feldspar - Obsidian - Agate -Turquoise - Amber - Jasper - Ivory - Jet - Moonstone - Opal - Topaz - Zircon - Onyx
Was this up before I wrote my background? If so I feel very stupid.
I have an idea. What about a group that believes that they should no longer be limited to the astral plane and seeks to build permanent Githyanki homelands on prime worlds? Those of the native barbarian inhabitants that are not wiped out are forced into servitute to help maintain the infrustructure. However, because lesser life forms are not to be trusted they've started to use psionic abilities to ensure better continued obedience. Some others in the group have come upon the idea of experimenting on the barbarians in various ways to make them more compliant and better workers. Because of the massive industry available to this group thanks to the barbarian workers they've been able to become very powerful very quickly.
What do you think?
What you are describing, DL, is the Apocalytes. I haven't taken the 'dominate graith psionicly' angle with them. Rather, they are classic conquorers, with many non-gith serving either for the money, or because their lives were spared in the Incursion, or the opportunity to have power over their fellow barbarians. The psionic domination angle has merit tho ....
Githyanki also traditionally have "issues" with essentially enslaving barbarians on a long-term basis. That depends on which published source you read, though. (Perhaps the githyanki attitude toward enslaving graith is itself contradictory.)
Well my idea was, they've come to view barbarians with such distain over the years that they've started to become lax in their principles. They'd start creating an empire using psychically dominated barbarians to do most of the work while all they did was command. The idea I was going for was that they would eventually become so corrupted by their hatred that they start to become what it is they most hate. Clever no?
Ummm ... sure ...
I could see it happening on a limited basis. I think it would be interesting if it started happening in one area, and the leaders of the Apocalytes turned a blind eye to it.
There is a do-or-die aspect to githyanki cultural psyche, though. They either kill you or spare you, and they only spare the worthy. The economic realities of the Incursion demanded that they spare agricultural professionals. In my own Incursion campaign, an order was issued that a graith in a fertile field wielding a farm tool and no armor was to be left alone. Of course, his crop was raid-worthy, but so long as the farmer ran outside and strarted digging in the dirt, the raiders would leave him be.
They killed anyone who wasn't in a fertile field wielding a farm tool and no armor? What about cities?
No, I never said they killed everyone who wasn't a farmer, I just said that they didn't kill farmers.
You said they only spare those who are worthy, and made an exception for the farmers because they needed them.
Who else did they spare?
Probably not. Anyone who can make things, grow things, or transport things that an army would prefer not to make/grow/move for logistical reasons probably. Also anyone who is actively fighting or gausing problems for the ghaik (or who could be made to do so with some arm-twisting and sword-poking)
What did they do with those who weren't useful to them?
Either slaughtered them or forced them to become refugees in other lands, I would assume. Githyanki have a cultural aversion to slavery, but not genocide.
They might even have been sacrificed, though I'm not sure if that would be the case in BoGr.
Nice summary!
The Unifists are a new addition, aren't they? I'm guessing that's where you wanted to have Gy-Nath at... and they also seem like they would appeal to Du'minh (though he would hope the People would reunite despite current order of day, not because of it).
I'd suggest adding a quirk or two to them, since they might come off as a bit bland (if you don't mind me saying so).