12:10pm Dec 30 2011 (last edited on 12:10pm Dec 30 2011)
Normal User
Posts: 3,642
It's the chance a successfully hatched egg has of having a mutant Creatu in it. P:
Like. A fresh egg has the lowest chance of hatching a mutant, but the highest chance of hatching in the first place, while a spoiled egg has a high chance of having a mutant in it if it hatches but is difficult to hatch at all. Most spoiled eggs fail. You're still more likely to get a mutant from a spoiled egg than a fresh one though. You just won't get much else.