Slime Rain is a minor event that consists of frequent spawns of Green, Blue, and Purple Slimes, and rarely Pinky. It occurs randomly, signaling its beginning with the message "Slime is falling from the sky!". Slime Rain continues until 150 slimes have been defeated, at which point King Slime will spawn. If King Slime has previously been defeated in the world, he will spawn after only 75 slimes have been defeated. The event ends shortly after he is defeated or despawns. All slime spawns from the event will be continuously hostile, unlike naturally spawned slimes.
While a Slime Rain is active, Green, Blue, and Purple Slimes will appear to fall in the background. The event can last anywhere from 9 to 15 in-game hours. If the player fails to defeat 150 / 75 slimes by the end of the Slime Rain, the message "Slime has stopped falling from the sky." will appear and the Slime Rain will end naturally without King Slime spawning. The event does not end if the player leaves the world.
A Slime Rain cannot be initiated manually, so in order for it to occur, the following criteria must be met:
- At least one player in the world has more than 140 maximum health and more than 8 defense (except in Expert Mode, where it can occur before meeting these criteria – albeit with a significantly decreased chance).
- None of the following events are active: Rain, Lantern Night, Blood Moon, Solar Eclipse, Frost and Pumpkin Moons, Goblin Army, Frost Legion, Pirate Invasion, Martian Madness, and Old One's Army.
A Slime Rain can only occur between 4:30 AM and 12:00 PM. It has a 1/225,000 chance of occurring each tick during this time, resulting in a chance of
12*3/25 (12%) each day. The chance is decreased in Hardmode, if King Slime has already been defeated, and for Expert Mode players that do not meet the criteria:
or criteria met
|Criteria not met|
or criteria met
|Criteria not met|
- Only Blue Slimes (including those spawned from a Slime Statue) and any of its variants that share the primary NPC ID value of 1 count toward the event total: Jungle Slime, Yellow Slime, Red Slime, Purple Slime, Black Slime, Baby Slime, Pinky, and Green Slime.
- Slimes killed by lava or traps will count toward the event total.
- If King Slime is summoned via Slime Crown during the event and killed, the event will end.
- In the event that the player is killed during the Slime Rain, there is a chance that King Slime will not despawn, especially if it is penned in by terrain or blocks. When the player respawns, King Slime will usually immediately teleport to the player's location if this has happened.
- In the event that the player is killed during the Slime Rain and King Slime does successfully despawn after hopping away, it is possible to continue defeating slimes and to cause King Slime to respawn. This means that the player must defeat another 150 slimes (or 75 slimes if King Slime has been defeated previously) before the Slime Rain ends.
- The Slime Rain can occur while a boss is alive.
- The Sticky Situation achievement will not be awarded if the event ends without King Slime having been defeated.
- If the player is in a biome that features special variants of slimes, those slimes will not rain from the sky and their normal spawn rates will not be affected.
- Slimes spawned by the Slime Rain are not affected by the enemy spawn rate slider in Journey Mode.
- The event can be avoided entirely by staying indoors or underground, as it can end without any player interaction after a certain amount of time has passed.
- The high spawn rate of slimes during a Slime Rain, including Pinky, greatly facilitates farming for Gel, Pink Gel, Slime Staff, and the slimes' banners. King Slime will also offer loot that is useful at the beginning of the game.
- An enclosed shelter with a 1×1 hole in the wall will allow the player to fire arrows, bullets, and use yoyos from relative safety. However, once King Slime spawns, it is advised to leave, as he can teleport into the shelter and trap the player.
- The spawn rate can be increased with a Water Candle and Battle Potion. Similarly, it can be decreased with Sunflowers, a Calming Potion, and Peace Candles.
- Making an arena with at least 2 layers is helpful, as the slimes would fall on the top to be easily farmed by the player. Once King Slime spawns, the player could go under the arena, in which the slimes would still be falling on the top of the arena, so they don't get in the way of the King Slime fight.
- The Slime Rain effect in the background can be seen before the event is announced if the player goes up high enough.
- Some slimes appear to spawn in the air above the player which results in them falling from the sky, giving the term "rain" a literal meaning.
- The Slime Rain is one of two events in Terraria that cannot be summoned via the use of an item, the other being the Martian Madness.
- Desktop 1.4.4: Increased the chance of occurring by 20%. Can now only occur between 4:30 AM and 12:00 PM.
- Desktop 126.96.36.199: Introduced.
- Console 1.0.933.1: Introduced. ()
- Console 1.0.750.0: Introduced. ()
- Switch 1.0.711.6: Introduced.
- Mobile 188.8.131.52: Introduced.
- Information taken from the Desktop 184.108.40.206.1 source code, method
Terraria.Main.cs. There may be inaccuracies, as the current Desktop version is 220.127.116.11.
- A tick is a time unit countable by the software. Most of Terraria's updating logic happens every tick. A tick has the length of 1/60th of a second, hence there are 60 ticks in a second and 3600 ticks in a minute.