True to its name, a Trumpet Arrowgun resembles a gold trumpet with an angular, diamond-shaped bell. It has two silver valves as opposed to the normal three, a silver mouthpiece and the slide of the trumpet acts as the handle and guard. The entire body of the weapon flashes yellow when Xigbar reloads. When Xigbar fires, the bell emits a flare of gold light, but the actual "bullets" are white, circular sound waves. A charged shot is represented by three large sound waves. The Trumpet's bullets produce yellow-orange sparks shaped like musical notes on contact with enemies, and gold ones on contact with anything else. When Xigbar reloads, a short trumpet solo is played.
As the description for Mystery Gear states that it brings out the user's personality, this may be a reference to the fact that Xigbar likes to "toot his own horn".
The Trumpet can fire twelve shots before reloading. Its ground combo fires two quick rounds at a time twice; oddly enough, one of the trumpets is pointed towards the air when fired instead of at the target. For the ground combo finisher, Xigbar spins around and fires two more shots accompanied by larger sound waves. The aerial combo consists of four shots fired forward, followed by a back flip and an aerial combo finisher of two more shots before landing.