Although rather pathetic in the early stages, when this enemy starts appearing in huge hordes, especially with their Knockback effect, they become an actual threat. The best way to counter this enemy is by using Anti-Red Units such as Fish Cat, Crazed Fish and Can CanCat.
Strategy[]
Assuming they don't move forward at all, Crazed Fish and Fish Cat actually have the perfect TBA to infinitely knockback Red Ball, making it a piece of cake to deal with. Alternatively, using units with Knockback Immunity or a longer range than its Omni Strike will make it practically unable to push.
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Gallery[]
Red Ball's spritesheet
Red Ball's moving animation
Trivia[]
This enemy, as well as White Ball and Metal Ball are based on the Japanese Sports Day event, Oodama Korogashi.