I like how you took the concept of a tower defense and add the necromancer tower + click to kill + click to revive theme/mechanics into account.
Even though I did not feel this game as a TD game, I think it has some good elements of action in it.
The art is simple, which is not problem, but I could identify which characters were allied and which were enemies. But I guess it worked, because they were fighting between them anyway (?)
Congrats on your game.