Level 25 is a poor puzzle. Tic-tac-toe is a solved game. Playing against a computer is just repetitive and frustrating, since the computer will almost always win/force a tie.
The "Save 2 Happys" level is poorly designed... more often than not, no "happys" appear to spawn. I assume they're simply spawning beneath the time bar or some such, where I can't see them. Other than that, it's like Warioware with less variation. 4/5.
Nice game, I enjoy it quite a bit, but the challenges aren't even difficult anymore, they're just infuriating. Starting with 5 health causes you to rely solely on luck, not skill. You cannot defeat an enemy with 50 health in one turn and nearly any attack card will drop you in one shot. If you make a follow-up, I'd look into that.
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 "The Necronomicon"){kind=icon}