MAGIC DUEL
It's a free online browser role-playing game. Can become quite addicting, although it's a little confusing at first. When you sign up, leave the promo code there, that will make you an adept of mine. Adepts strengthen your character so once you get the hang of the game, be sure to share it with your friends.
In this game you explore a world (it's pretty big), you collect monsters which act as your minions and do your battles for you (sort of like Magic: The Gathering), you can collect items, there are puzzles, all-in-all it's a cleverly-designed game that keeps you coming back.