Board Thread:Plants vs. Zombies 2/@comment-1764483-20150914192504/@comment-25154254-20150916010509

They do not crush or kill each other. The unnecessary of them are outside of the lawn. I believe PopCap has installed a system that makes all non-speed zombies instantly die if they are unable to spawn at the 9th column. In Endless Zones, there are a lot of zombies spawned at very far columns, not the 10th column like we usually think. It is possible that the Zombie Kings and Fisherman Zombies are spawned there, but because they are impossible to defeat, they are made to instantly die. If someone notices closely, there will Zombie Kings' dying head on the rightmost screen. If EZ existed in Chinese version, this would be explained very clearly.

For some reason, I think they act like "plants".