Steal An Egg Mutations Guide — Every Multiplier and How to Get Them

What are mutations in Steal An Egg?

A mutation is a permanent income multiplier stamped on a pet. Every hatch rolls three independent traits: the pet’s rarity (its base rate), its weight in kilograms (the size system), and its mutation. The mutation then multiplies the weight-based income — so the strongest end-game pets combine a huge weight roll with a top multiplier. You can see both the weight and the mutation before the hatch animation finishes, which is why veteran thieves watch the bar instead of walking away.

Every mutation and its multiplier

The first five multipliers below are confirmed by two independent guides. The last three are community-documented estimates and are labelled as such.

Shell colour tells you before the hatch: eggs that spawn with a rainbow or golden tint hatch with a guaranteed mutation. Silver, Golden and Rainbow can appear on eggs in any biome, which is why checking shell colour is free money — a habit the beginner guide drills early.

The seven ways to get mutations

1. Hatch mutated eggs. Silver, Golden and Rainbow roll naturally on hatch. Patrol nests after a spawn refresh and grab tinted shells.
2. Fuse three same-mutation pets. The Fuse Machine keeps the shared mutation and can roll a heavier result. Fuse mismatched pets and you can lose the mutation — the machine only guarantees what all three inputs share.
3. Admin Abuse events. Developer-run Saturday events where admins spawn chaos and rewards, including mutated eggs. Free multiplier chances, no cost.
4. Sakura Incubator. The Cherry Blossom biome’s incubator applies Bloom or the 3x Spirit Bloom (~2.5% chance) to an egg before it hatches — the only source of both. You need a Crane pet and serious Speed to reach it.
5. Parasite Egg. Feed the Hungry Frog five infected eggs during the Titan Temple event for a 1.5% chance at a Parasite egg, worth about 3x.
6. Rift Boss consumables. Trade Boss Tokens from the Abyss Overlord fight in The Rift for consumables with a 10% Fractured chance — roughly three runs per proc.
7. Scrambled consumables. Collect Samples from Dr Scramble’s drones in Dr Scramble’s Laboratory and trade them for consumables with a 10% Scrambled chance, about four to five per run.

What to fuse first

The Fuse Machine rewards patience: three Rainbow pets produce a Rainbow with a weight reroll, which is usually better than hatching for a fourth Rainbow. Save your same-mutation trios until you have three you would be happy to keep either way, and never feed a mutation you cannot replace into a mismatched fuse — the result can come out plain.

How mutations fit the income formula

The full stack is: rarity sets the base, weight in kilograms scales it, the mutation multiplies the total. That is why the community phrase is “Huge Silver beats small Rainbow” — a pet near a million kilograms at 1.25x out-earns a light pet at 2.5x. Combine a heavy roll, a top mutation and a late biome’s egg values, and the developer’s showcase figures like the $89,121Sp/s Yeti Egg become reachable. The pets guide breaks the three-trait system down in detail.