Overall bleh. It takes about 2 minutes until the zombies require a ridiculous amount of hits to defeat. Extra ball powerups are random, which makes getting far random. It feels like I am playing a slot machine, and that's pretty boring.
Overall 2/5. By day 11 the difficulty is so great that even fully maxed units are easily killed by the enemies. It becomes completely impossible to win. The difficulty balance needs serious work.
Getting the easter eggs is way, way, way, too hard. I can't even do the second one with the spike walls after half an hour of trying. Overall this game has an interesting idea but the gun is just too hard to control.
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 "Monster Hordes"){kind=icon}
 "No Time To Explain"){kind=icon}
 "Demons vs Fairyland"){kind=icon}
 "Cursed Treasure 2"){kind=icon}
 "Aisleen"){kind=icon}
Got it, I will be more careful next time designing an enemy.