Hi! My name is Aaron, and I am new here, though a long-time member of ENWorld. I DMed Planescape back when it first came out, and ended up giving away my Planescape collection to a friend's younger brother when I moved. Yeah, he was stoked.
And now I've begun DMing a 4e Planescape game. Heh. Perfect. Fortunately I found a copy ofthe original boxed set and had purchased some PDFs way back, so coupled with my memory and the help of the planescape online community I should be able to run a solid game.
We're a few sessions in, with a party consisting of a pixie cavalier and wilden druid (both "fey beast tamers"), a modron artificer named 2XB2 and a Buddhist minotaur monk (both hailing from Mechanus/Nirvana), and a prime halfling rogue on a quest of vengeance. The first four are tied together by being in the retinue of Blessed Karadja, a nymph sidhe noble who is trying to start a new sect in Sigil. The rogue just joined the party as a mercenary. I started them at sixth level.
I'm just scratching the tip of the iceberg, but I don't want to dump a bunch a text in my "hello" post
Any advice from old pros about running a planescape sandox?
Sandboxes still have edges to keep them contained, so it may help if you decide to stick to an area to focus on, rather than having the entire range of inner and outer planes available. For instance, each sect and faction tends to have a home plane in addition to having a presence in Sigil. What plane would it make sense for this new sect be based? And what's the major belief of this new sect that ties it together?
Oh, and welcome to Planewalker!