Poptank is a Badnik that featured in the Knuckles Knock-Out Special. Bearing a heavy likeness to a Turbo Spiker, this robot from Knuckles Chaotix used its large shell to fire artillery rounds at its enemies. Poptank hails from the Marina Madness area and moves around on caterpillar tracks.
Although not featured in any comic strip, Poptank appeared in the Badnik Alert! feature. The special gave the Badnik a Danger Rating of 3 (out of 5), stating that "one thing this piece of heavy artillery won't be firing is heavy lemonade"!