The Celebration is a Hardmode post-Moon Lord Launcher that fires two rockets at once (but only consumes one unit of rocket) that travel a short distance before exploding. When the rockets detonate, they display patterns and colors similar to fireworks. It has a 1/9 (11.11%) chance to be dropped by the Moon Lord.
The Celebration has a base 14% critical strike chance as opposed to the usual 4%.
Its best Modifier is Unreal.