Sands of Tchavaal
For the complete rules, go here.
From level 1 to 6, Sands of Tchavaal is played exactly like regular Pathfinder. However, the characters can never rise above level 6, instead gaining feats as they recieve more experience. For every 5000 points of XP a 6th level character gains, s/he may select a new feat.
Feats that require a character to be over level 6 are unavailable to all characters in Sands, but some custom feats have been added to simulate certain lvl 7-8 class features. This means that a characters power level can rise above 6th level, but at the level cap the progression becomes very slow.
These rules apply to all PCs and NPCs of the character races from the Core Book, but not monsters. Creatures with more than 6 HD or spell like abilities of spell levels higher than 3 are either fearsome threats to civilization or mythical beings of song and legend. GMs are also allowed to give more than 6 class levels to powerful outsiders and the like, but this should only be done in rare and extreme cases.
Epic 6 Feats.