Sporulator

'Note: nothing on this page is confirmed. This is all speculation due to the tank's name and pre-evolution.'

 is a Tier 5 Tank branching from the Bubble Gun at level 60.

Design(not confirmed)
looks like the Bubble Gun with Machine Grower's "grower" on it.

Technical
operates very similarly to Bubble Gun, but upon killing an entity it leaves behind many bubble bullets, identical to the ones its bullet fires. This effect will trigger if the entity is killed either by the main bullet or its bubble bullets.