Racial substitution levels are optional rules originally introduced in the Races of ... product line, which allow you to flavor your class levels based on your character's race.
A substitution level is a level of a given class that you take instead of the level described for the standard class. Essentially, a substitution level grants you an alternative class feature in place of the standard class feature normally gained at that level. Some substitution levels only modify the standard class feature instead of replacing it completely. The only prerequisite for taking a substitution level being of the proper race and class level.
When a substitution level modifies Hit Dice size, this modification applies only to that level, not all levels of the class. Conversely, when a substitution level modifies the list of class skills, this change applies to all levels of the class.
GITHYANKI FIGHTER:
The unique environment and social customs of the warlike githyanki race can result in the development of unorthodox combat techniques.
1st Level - Greater Coordination (Ex): You can take advantage of your weightless environment, using all three dimensions for combat maneuvers. When you flank a foe on the Astral Plane, you get a +4 flanking bonus on attack and damage rolls.
This class feature replaces the standard 1st-level bonus feat.
4th Level - Armor Focus (Ex): Select one type of armor. You treat its maximum Dexterity bonus as if 2 points higher.
This class feature replaces the standard 4th-level bonus feat.
8th Level - Queen's Grace (Su): You have proven yourself a worthy knight in the eyes of your undying monarch, and your devotion to her is religious. You can add your Charisma modifier to all saving throws.
This class feature replaces the standard 8th-level bonus feat.
GITHYANKI PSYCHIC WARRIOR:
Second only to the thri-kreen, githyanki have a long-standing tradition of training psychic warriors. They call these characters "gish", and respect the balance they seek between physical and mental combat techniques.
2nd Level - Gish Focus, Defensive (Ex): When you expend your psionic focus as part of manifesting a power (for example, using a feat such as Power Penetration), your manifestation does not provoke an attack of opportunity.
This class feature replaces the standard 2nd-level bonus feat.
5th Level - Gish Focus, Offensive (Ex): When you expend your psionic focus as part of an attack (for example, using a feat such as Psionic Weapon or Deep Impact), there is a 50% chance that you automatically regain the focus if the attack is successful. If the attack misses, the psionic focus is expanded normally.
This class feature replaces the standard 4th-level bonus feat.
8th Level - Weapon Devotion (Ex): You have a +1 morale bonus on weapon damage rolls with weapons you have crafted yourself. Additionally, any psionic properties you place on such weapons cost 25% less.
This class feature replaces the standard 6th-level bonus feat.
GITHYANKI RANGER:
Among the githyanki, rangers are usually less nature-oriented, and more of the "genocidal bounty hunter" frame of mind. Few have the necessary wisdom to cast spells, but those that do typically call upon their connection to the Lich Queen, and not to a nature-related deity.
Class Skills: Add Intimidate and Knowledge (the planes). Remove Knowledge (dungeoneering) and Knowledge (geography).
1st Level - Racial Empathy (Ex): You can use wild empathy against animals and magical beasts native to the Astral Plane, and red dragons native to any plane; no penalty is applied. However, if you use wild empathy against animals or magical beasts native to planes other than the Astral, a -4 penalty is applied to the check.
This class feature is a modification of the standard wild empathy ability.
5th Level - Enemy of the People (Ex): If you have both the githzerai and the illithid designated as your favored enemies, the bonuses against both become +4. From this point on, whenever you improve the favored enemy bonus against one of these creatures, it is automatically improved for the other as well.
This class feature is a modification of the standard favored enemy ability.
7th Level - Astral Stride (Ex): On the Astral Plane, your speed is equal to 10 ft. x your Dexterity score (instead of 10 ft. x Intelligence score).
This class feature replaces the standard woodland stride ability.
13th Level - Improved Evasion (Ex): As the rogue's ability.
This class feature replaces the standard camouflage ability.
15th Level - Analyze Portal (Sp): You can use this spell-like ability at will.
This class feature replaces the standard hide in plain sight ability.
GITHZERAI MONK:
Among the chaotic githzerai of Limbo, the lawful monks have an important role. Their focus on order is believed to help maintain the stability of the chaos-shaped communities.
Class Skills: Add Chaos-Shaping and Survival.
5th Level - Purity of Space (Su): You are immune to the sporadic element trait of a plane. You do not drown when your environment assumes the water-dominant trait, do not take fire damage when it becomes fire-dominant, do not suffocate when it becomes earth-dominant, and breathe normally even when it becomes air-dominant with a non-breathable atmosphere.
This class feature replaces the standard purity of body ability.
13th Level - Diamond Mind (Ex): Your racial power resistance is more effective against mind-affecting effects, equaling 11 + your character level. Against all other effects, it is still equal to 5 + your character level.
This class feature replaces the standard diamond soul ability.
16th Level - Ki Strike (Axiomatic) (Su): When attacking creatures of the chaotic subtype, your unarmed strike functions as an axiomatic weapon.
This class feature replaces the standard ki strike (adamantine) ability.
GITHZERAI ROGUE:
Githzerai are much more agile than most other humanoids, and their fluid, mobile fighting style reflects that. Many rogues are also interplanar travelers, whether alone or as part of a rrakkma band, and learn to discern portals with ease.
Class Skills: Add Chaos-Shaping, Knowledge (the planes), and Survival. Remove Disguise and Forgery.
1st Level - Mobile Sneak Attack (Ex): You deal an additional +1d6 points of damage (a total of +2d6 at 1st level) on all sneak attacks you make during any round in which you also move at least 10 ft. You deal 1d6 points less (0 at 1st level) on sneak attacks you make during any round in which you do not move at least 10 ft.
This class feature is a modification of the standard sneak attack ability.
3rd Level - Greater Coordination (Ex): You can take advantage of your weightless environment, using all three dimensions for combat maneuvers. When you flank a foe on Limbo, you get a +4 flanking bonus on attack and damage rolls.
This class feature replaces the standard 3rd-level sneak attack improvement. From this point on, your bonus sneak attack damage is 1d6 points lower.
3rd Level - Portal Sense (Ex): You have a +1 bonus on all Search and Spot checks made to detect a portal.
This class feature replaces the standard trap sense ability. Whenever the trap sense would improve (such as to +2 at 6th level, etc.), portal sense improves instead.
GITHZERAI WILDER:
The primary psionic manifester among the githzerai is the wilder, not the psion. Whether reveling in the dynamism of Limbo's chaotic energies, or seeking to stabilize and control them, githzerai wilders tend to take even greater risks in stretching the limits of psionic potential than those of other races.
Class Skills: Add Chaos-Shaping and Survival.
1st Level - Chaos Surge (Su): When invoking a wild surge on Limbo, your manifester level increase for that manifestation is 2 points higher. Should this cause psychic enervation, the number of power points you lose is equal to your effectively increased wilder level.
This class feature is a modification of the standard wild surge (and psychic enervation) ability.
2nd Level - Inertial Reaction (Ex): Whenever you take hit point damage, you can activate your inertial armor psi-like ability as an immediate action (provided that you haven't already expended the available daily uses of the ability).
This class feature replaces the standard elude touch ability.
4th Level - Shaping Euphoria (Ex): When you invoke a wild surge on Limbo, you gain a +2 morale bonus on Chaos-Shaping checks for a number of minutes equal to the intensity of your surge.
This class feature replaces the standard surging euphoria ability. Whenever surging euphoria would improve by +1 (at 12th and 20th level), shaping euphoria improves by +2 instead.
Very, very nice. I especially like the githzerai wilders. Would it be kosher to use substitution levels to say that githzerai monks don't have to be lawful?