Benefits
Beautiful concept. Careful game programming and strategy. Music is awesome. The author obviously took a great deal of care.
Concerns:
Game lags too much for the activity. That is a big problem, although it is slow to begin with. 2x speed and pause button would help.
HINTS TO WIN LEVELS WITHOUT LOSS
Advanced units such as Alchemist and Necromancer are under-powered AND over-priced. They add nothing to any map except impoverishing the bank.
Better to fill out the board and update all mages. KEEP ALL MAGES OF ONE KIND TOGETHER, as the specials do not stack. The only exception is the red fire mage, since it is a splash, not an infection.
This strategy is the only one I could find to beat the last Evil stronghold. Fooling with advanced units was a waste of time.