Hollow Earther

 is a Tier 5 Tank that upgrades from Antivaxxer and Cytochrome at level 60.

Design
The looks like the Antivaxxer but with an additional small barrel added to the tip of its stack of mini barrels. Its body is also a hollow circle like.

Technical
As indicated by its body, the is immune to knockback.

As the



 * The can be played similarly to the Mitochondrion but with an extra trap barrel.

Trivia

 * This tank is named after a conspiracy theory that the interior of the Earth is actually hollow. This is referenced further by its knockback immunity, which is indicated by making the tank body literally hollow.
 * This and Glass Booster are the only Knockback Immune Tanks that have ranged weapons. All of the others are either Lancers or Smashers.