Celebration

The Celebration is a rocket launcher dropped by the Moon Lord. It fires two rockets at once that travel a short distance before exploding. When the rockets detonate, they will have patterns and colors similar to fireworks. The best modifier is unreal.

Trivia
The Celebration could be a reference to My Little Pony. One of the main characters, Pinkie Pie, owns a "party cannon" which has been shown in the series to possess offensive capabilities.