Besides the great animation and that it's not a completely terrible concept, this game is horrible.
1. All of the clicking becomes too much very quickly. It would be better if it was entirely an idle game, not just the help you hire being the idle part.
2. It's incredibly stupid that once you kill a type of zombie that all of your upgrades reset when you move on to the next zombie. That's where the worst of all of the insane amount of clicking is.
3. I don't know why there's a timer with the second stage of the game. It's annoying that the game keeps stopping after the timer runs out. Not to mention that the zombie's health has to regenerate. The best possible option for stage two would've been to put the baby zombie in stage one. It has not as much health as the first zombie, so it should've been in the first stage and the whole timer element should've been scrapped. There could be more stages with a timer, but I don't think I'll ever know because I stopped on the third stage. It's just not worth it.
4. To explain even more why this game just isn't worth it, some of the medals are EXTREMELY hard to get. I'd be lucky if someday I could get through this game one time and get the medal for it. THREE or FOUR times, though? That's insanity. I'm willing to bet that some of the users who got those medals used a hack to get the medals without playing the game. It's just WAY too much to ask for. I can't see anyone actually going through with it.