Terra Codex
// the open codex of terraria
// Pre-Hardmode event

Slime Rain

Trigger
Random ~1/450k chance per second during daytime, requires at least one player at 120 max HP.
Duration
9–15 hours until 150 slimes killed (summons King Slime)
Spawn changes
Constant slime spawns on the surface across all biomes.
Rewards
King Slime summon; Slime Crown drops; cosmetic slime banners.

Frequently asked

How do you start a Slime Rain in Terraria?

Random ~1/450k chance per second during daytime, requires at least one player at 120 max HP.

How long does the Slime Rain last?

9–15 hours until 150 slimes killed (summons King Slime)

What are the rewards from the Slime Rain?

King Slime summon; Slime Crown drops; cosmetic slime banners.