Boomer

Description
The Boomer zombie is a late game zombie only appearing in Hard, Insane and Gladiator event. It first appears on wave wave 34 on any map. (Except Easy and Normal mode.)

At first this zombie may look like he's not a threat but he can be a problem if he's grouped with lots of strong zombies as he can stun all your towers when killed, letting other strong zombies to pass.

Appearance
The Boomer looks like a derpy chubby zombie that wants to give you a hug. But do not be fooled as he can give a big explosion if killed.

Strategy
Most of the time Boomer will be one of the last zombies to appear in a wave but is mostly grouped with strong zombies. When the boomer appears makes sure your team has a Medic as she has an ability that can remove stun letting your towers kill the rest of the zombies.