Dungeon Siege franchise is one of those I gladly come back to from time to time. It's an RPG genre where the first game was released all the way back in 2002. It has three games in it (not counting expansions). The first game is somewhat a hack & slash type of game where you do have stats like Strength, Dexterity, and Intelligence. But that's about it, nothing special. In the second game, they realized this was not good enough and added skill trees, which made it so much more interesting and forced you to play over and over, testing new combos.