Board Thread:General Discussion/@comment-5175884-20131005184425/@comment-24508466-20140316185738

My theory is: Dr. Zomboss created one unique zombie for every period.

Egypt: Explorer from future (Relatively)

Pirate: Automatic imp cannon (It isn't controlled by anyone)

West: Bull (He's a robot)

China: Blew Zombie (Yep, explosives exist in china, but shape of bomb he holds in his hands in more modern)