What are some good iPod Touch games that are cheap and long-lasting?

Games like Zenonia, Rolando, Blocked, and Zombieville USA.



Also, does anyone know exactly when Zenonia 2 is coming out? Yes, there will be Zenonia 2, sometime in Fall.



Anyways, heres a list of games I already have, so make sure not to include them:

Rolando, Fieldrunners, Touchgrind, Oregon Trail, 7 Cities TD, The Creeps!, AppSniper (Not a game), Blocked, Bloons, Moron Test, Classics, HeavyMach, geoDefense, Pocket God, Must.Eat.Birds., Underworlds, Price Is Right, iCopter, Leaf Trombone, StickWars, iDracula, PapiJump +, Flick fishing, and topple 2. Phew, long list.



I am mostly in to RPG's, shooters, puzzles, and tower defenses.What are some good iPod Touch games that are cheap and long-lasting?
Sims 3.

'Nuff said.