The Xolstar is a spaceship that is capable of flight in space, and probably supports a pilot. The ship itself looks more like a jet plane, with a mahogany cockpit. There is a rocket booster situated on the back, propelling Xolstar forward.
Xolstar will move forward without the player's control. Pressingallows it to travel forward at a faster pace. It can also move vertically if or are pressed, and when doing so flips ninety degrees. When Xolstar loses all three lives, it detonates in a few blue explosions.
From an unseen side of the ship, Xolstar can fire lasers at enemies, most of which can be destroyed with one shot. The lasers are also able to destroy asteroids in two shots, which cause Xolstar to lose a heart if contact is made.
In one of the later levels of Mega Mash, Xolstar can obtain a power-up that upgrades its weapons and defense mechanisms. Instead of one laser firing forward, the power-up allows Xolstar to fire three lasers: one forward, one diagonally up and one diagonally down. This makes it easier for the Xolstar to kill enemies, and also makes a makeshift shield to make him immune to all damage.