Red Rocket

Despite the name, no launcher accepts these. You place the rocket on the ground like a piece of furniture and then either activate it by hand or run wire to it. Either way it climbs straight up and bursts, either at the top of its arc or the instant it clips a ceiling, so an indoor display needs headroom or the effect happens at eye level. Each one is spent after a single firing.

The burst hurts. It counts as ranged damage, scales with your ranged critical strike chance and picks up ranged set bonuses, so a floor packed with them will strip a boss health bar in seconds. The problem is delivery. You have to hold the target over the carpet long enough for the rockets to travel and detonate, which rules out anything that dashes, flies off or teleports.

There is a multiplayer catch worth knowing before you build a trap room around them. The bonuses only apply when the game can attribute the rocket to a player, which means you triggered it by hand. Anything fired by wire falls back to its base output, so an automated array throws away every point of gear you are wearing.

The Party Girl stocks these once the world is in Hardmode. Red is the plain option alongside blue and green, and the color only changes what the burst looks like. The explosion is much wider than what a Fireworks Box throws out, so a few of these wired to a timer cover a whole build where the box only decorates one corner. The same projectile shows up on the Celebration, which is why the launcher feels so festive.