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Its radiance is so lovely it makes you sick.

The Rad Slime is a Slime found exclusively in The Indigo Quarry, and in The Wilds entirely as Saber Largos. Unlike other Harmful Slimes, they do not deal damage directly, but when exposed to their aura for long enough the player will start taking constant damage as long as they remain within the aura.

Slimepedia Entry

It's unknown if rad slimes, sometimes called 'raddies,' came to be from external radiation sources or from something naturally occurring within the Far, Far Range. Regardless, rad slimes emit such a potent aura of radiation they glow in the dark!

Rancher Risks:
A rad slime's radioactive aura can induce rad poisoning to a rancher if they remain within it for too long. Ranchers are advised to monitor their rad exposure levels when handling these green globs of gamma goo as extended exposure can cause serious bodily harm, or worse.

Given that raddies are basically mobile batteries, it's no surprise that corporations value rad plorts for their incredible energy-producing capabilities. Most rad plorts get turned into 'plortonium' and everything from the latest holophone to a radwave microcook system runs on the stuff.


Multiple rad slimes can lead to a very quick knock-out.

The Rad Slime is easily identified by its vibrant green coloration and the radiation aura surrounding it. When the aura is walked into, it produces a radiation meter that slowly fills up; filling up more quickly if exposed to more rad slimes. When filled, it deals 10 damage regularly, with increased frequency with exposure to more rad auras. Due to this, it can be extremely dangerous to ranch rad slimes without measures in place to avoid extended contact.

The aura can temporarily increase in size every two to three in-game hours, telegraphed by the wide green smile on the slime; the frequency at which it does this increases with higher agitation, capping at every 30 in-game minutes at 100% agitation. The aura returns to its normal size after 10 in-game minutes. The radiation aura can be temporarily nullified with Water or Ancient Water for 20 in-game minutes.

Like other slimes, a rad slime mainly hops around aimlessly until it begins seeking out food when hungry, and will seek out plorts it does not produce to induce transformation into a largo. Rad slimes can respond in awe at a freshly-transformed largo and a slime activating a Slime Stage, and pure slimes have the ability to stack with other slimes unless it becomes a largo. A rad slime can be applied with Fashion Pods and can respond to Slime Toys, with it favoring the Power Cell or a DLC Slime Toy if it is wearing its associated Fashion Pod.


  • Exposure to more Rad Slimes speeds up the increase of the radiation meter, and increases how frequently one takes damage once it reaches full capacity. This makes it difficult to go into a Corral and vaccing a Plort. It is better to get a Plort Collector than risking getting damaged by radiation.
    • Note that Rad Gordos cannot have their radiation nullified.
    • A Rad Gordo's radiation field will get bigger the more you feed it.
    • A Rad Largo will not induce radiation if it is held on the Vacpack.


  • 1.2.0 - Fixed bug where it was possible to keep receiving radiation after teleporting while in rad auras.
  • 0.3.0 - Rad Slimes are re-added and can be legitimately obtained; Effects of their radiation aura improved.
    • 0.3.0c - Larger spawn rates of them in Indigo Quarry.
  • 0.2.0 - With the removal of proto Indigo Quarry, they were temporarily unobtainable by normal means. They were still visible in menu, however.
  • Before 0.2.0 - Addition of them into the game.


The Rad Slime's name is a double entendre. The nature of the slime is radiation, while its short description in the slimepedia entry uses the term radiance. However the pronounciation of the word may reference the 1970's slang term of the word radical. Having Oca Ocas as their favorite food - which are partly based on potatoes - may be based on the well-known potato battery often created in educational settings, since potatoes are among one of the foods that can produce low levels of electricity under the right conditions.

Rad Slime's Secret Style - Radiant - continues the radiance pun on its own name. It is a brighter green, which indicates it is more healthy than in its standard appearence.


  • Contrary to popular opinion, a Rad Boom Largo will not produce a larger explosion - nor is it any more dangerous - than any other Boom Largo.
  • Despite being able to remove their radiation auras by shooting them with water, their radiation isn't nullified when immersed in a body of water, such as a Pond.
  • A Hunter Rad Largo will have a unique face when expanding its aura.
  • If a Rad Slime is expanding its aura and is splashed with water, the aura will not be nullified until it has finished expanding.
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