i found a bug, at wave 30. I was buying all upgrades and all weapons to get all the achievements. But the zombie STOP in the middle of the game and i can shot em but makes no damage, and after 20-30 seconds it start to MOVING again yikes!
i have a suggestions:
1. If developer watching this. please make the background plain black, it's hard to see which one is enemy, which one is rainbow pixels and which one is BACKGROUND. thx
2. I think Seeker's attack power is too strong.
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