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War Chariot Zombie is the fourth boss in The Great Wall of China in Plants vs. Zombies: All Stars. It is an Imp standing on a big chariot (without the horse). It attacks by throwing bombs on plants. It has six stages of health and takes four turns to activate its boss skill, which is shooting all plants with the chariot's cannon.
Imp atop the war chariot
HD War Chariot Zombie
Two War Chariot Zombies, one showing its cannon
About to throw a bomb to attack
After throwing the bomb
War Chariot Zombie's boss skill (stage 1)
War Chariot Zombie's boss skill (stage 2)
Plants being damaged by its boss skill
A destroyed War Chariot Zombie (Note that the Imp has been tossed into the sky instead of dying)