Brick Breaker

 is a gun that fires bouncing, piercing turtle shells.

Trivia

 * This weapon is a reference to the Mario franchise of video games, well known for hiding items in nondescript, breakable bricks.
 * The weapon is also possibly a reference to Breakout, which is also known as Brick Breaker on many platforms.
 * The synergy is likely a reference to the Mario Party series of Mario games.
 * The name of the achievement that unlocks this gun is a reference to the game Castle Crashers.