Straightmute

 is a Tier 5 Tank that upgrades from Airhorn and Nightworker at level 60.

Design
The has an identical front barrel to the Nightworker, but with the addition of Airhorn's rear decorative barrel.

Technical
As a Nightworker branch, the can become invisible by staying still. It fires blocks that seem identical to Airhorn's.

Trivia

 * This tank's name refers to a special implement used to reduce the volume of brass instruments such as horns.