Knave (1st Ed)
Attribute/Stat Based (STR, CON, PER, etc) Dice (Various)
Knave is a rules toolkit...for running old school fantasy RPGs without classes. Features include:
High compatibility with OSR games. If you have a library of OSR bestiaries, adventure and spell books, little or no conversion is needed to use them with Knave.
Fast to teach, easy to run. If you are introducing a group of new players to OSR games, Knave allows them to make characters and understand all the rules in minutes.