Five Torches Deep OGL Forbidden Lands Spears Of The Dawn Low Fantasy Gaming Thirteenth Age Castles And Crusades Dungeon World D&D 3.5 Scoundrel (Rogue) Prestige Classes D&D 3.5 Scoundrel (Warrior) Prestige Classes D&D 5e Pathfinder 2

Archetypes

In Pathfinder, archetypes are semi-multi-classes

Pathfinder 2 Core Archetypes Pathfinder Advanced Player's Guide Archetypes Ultimate Wilderness Archetypes

Codex Martialis builds

Codex Martialis Codex Martialis