Bloodflower

Bloodflowers are non-damage dealing plants that increase the damage of surrounding plants when those plants kill enough zombies.

Overview
Plants that are in a 3x3 reach of Bloodflower get their damage doubled when they've defeated more than 20 zombies. They will continue to be in the powered-up state until Bloodflower is removed from the board. Defensive, instant-use, non-damaging, and mobile plants are not affected by Bloodflower's aura, and neither is Blood-shroom.

Plant-Food Ability
Bloodflower is permanently affected by Plant Food. In its Plant Food state, all plants in a 3x3 radius of Bloodflower will have their damage doubled, even if they haven't taken down 20 zombies.