From the introduction:
Welcome to TIER, the enhanced role-playing game. You might be wondering “What makes this game different from other role-playing games?” The answer is “everything”. Imagine a character you would like to create and this game has a way to do it. You begin with one class that is completely customizable. This class, for all purposes, is a blank slate. It only provides basic statistics and allows you to add on whatever you want in order to create your ideal character. You begin by choosing 3 Masteries that give you specific abilities. As you level up, you will gain more Masteries. However, the game has over 100 Masteries to choose from, which will make each and every character different from one another.
Fairly complete rebuild system based on D&D 3.0/3.5 OGL