Best replay value on iPhone

Defender Chronicles has perhaps the best replay value of any tower defense game on the iPhone. This is due to the fact that it requires a steady learning curve to complete the highest level, but perhaps even more so because of the "levelling" nature of the game - generals gain experience and skills, and every victory (and, to a lesser degree, loss) earns tokens which can be redeemed for artifacts which make the generals ("heroes") more powerful. The player decides where to invest tokens and skill points. The new version adds another hero and one more site.

Godo Stoyke about Defender Chronicles - Legend of The Desert King