Trashcannon

 is a gun that fires a trash bag, which explodes into 6 poison projectiles flying 60° apart from each other that create pools of poison.

Trivia

 * If the player has Ser Junkan, it causes an unknown effect.
 * The synergy is a reference to Oscar the Grouch from the show Sesame Street, who lives in a trashcan.
 * This weapon is likely a reference to the Junk Jet from Fallout 4 as well.