Chillin Chilli in Steal an Egg

The Chillin Chilli Egg is the Mythic-rarity egg of the Volcano, and the pet inside it is Chillin Chilli. Volcano is zone 6 of 12 on the wiki's Biomes list; the wiki lists its entry requirement as 700K speed, and the nests there are watched by the Cerberus.

Base income is $55K/s. Among the 8 pets tagged Volcano on the wiki that puts Chillin Chilli at number 4 — Lava Dragon tops the Volcano at $100M/s. Remember the game multiplies this base by the size roll and by the mutation, so two Chillin Chillis can earn very different amounts.

With a colour mutation and no size bonus, the same Chillin Chilli would earn roughly: Silver ×1.2 ≈ $66K/s, Golden ×2.5 ≈ $137.5K/s, Rainbow ×3.5 ≈ $192.5K/s (multipliers from the wiki's Mutations page; arithmetic is ours). Add a Giant (×3) or Huge (×5) size roll on top and the numbers multiply again.

Hatching it pays a one-off reward of +33k Speed, $5.5m, and the egg takes 7m to grow in the pen. That reward is the reason low-income eggs are still worth stealing early: the speed bonus is what gets you into the next zone.

Mythics are the eggs other players come to steal. Bear traps around the pen are the cheap insurance (max 3, 7-second hold).