Regular mutations roll randomly when a Brainrot is obtained, while some event mutations use special mechanics. Nerd is crafted through the Nerd Machine instead of rolled. There are 9 regular and 12 event-exclusive mutations.
Available through normal gameplay. Higher luck and Perfect Kicks improve your chances.
Event mutations are tied to limited-time events or their machines. Most are rolled during an event window; Nerd is guaranteed by completing its Nerd Machine recipe.
| Mutation | Type | Tier | Multiplier | 1-in-X | Approx % |
|---|---|---|---|---|---|
| Gold | Regular | Common | 1.5x | 1 in 10 | 10.00% |
| Diamond | Regular | Uncommon | 2x | 1 in 25 | 4.00% |
| Plasma | Regular | Rare | 4x | 1 in 33 | 3.03% |
| Molten | Regular | Epic | 6x | 1 in 125 | 0.80% |
| Radioactive | Regular | Legendary | 8x | 1 in 333 | 0.30% |
| Shadow | Regular | Mythic | 12x | 1 in 2,000 | 0.0500% |
| Electrified | Regular | Godly | 16x | 1 in 5,000 | 0.0200% |
| Rainbow | Regular | Celestial | 40x | 1 in 20,000 | 0.0050% |
| Astral | Regular | Ultimate | 50x | 1 in 50,000 | 0.0020% |
| Void | Event | Event | 12x | 1 in 500 | 0.20% |
| Enchanted | Event | Event | 12x | 1 in 500 | 0.20% |
| Virus | Event | Event | 14x | 1 in 800 | 0.13% |
| Wet | Event | Event | 16x | 1 in 1,000 | 0.1000% |
| Alien | Event | Event | 22x | 1 in 2,500 | 0.0400% |
| Phantom | Event | Event | 25x | 1 in 8,000 | 0.0125% |
| Bacon | Event | Event | 30x | 1 in 5,000 | 0.0200% |
| Heavenly | Event | Event | 32x | 1 in 10,000 | 0.0100% |
| Undead | Event | Event | 35x | 1 in 12,000 | 0.0083% |
| Volcanic | Event | Event | 35x | 1 in 8,000 | 0.0125% |
| Block Cup | Event | Event | 38x | 1 in 15,000 | 0.0067% |
| Nerd | Event | Event | 45x | Nerd Machine recipe | — |
Astral is the rarest listed regular mutation at 1 in 50,000 with a 50× multiplier. Event availability and odds vary by limited-time event.
For randomly rolled mutations, use Perfect Kicks, Global Luck Events, and the Mutation Luck Gamepass (139 Robux). Nerd is crafted separately in the Nerd Machine with 3 matching Plasma-or-better Brainrots, 350 Score, and a 30-minute wait.
No. A brainrot can only carry one mutation at a time. There is no stacking or replacing.
The 12 event mutations are tied to limited-time events or event machines; check the event schedule and each mutation description for availability.