User blog comment:BannedLagiacrus/Discussion of the Week: Monster Mutations/@comment-24825569-20140429204404

mhe, the Emerald Congalala turns green the same way the real world Sloths does, thanks to some species of algae that grows on their pelt.

For the Frontier G-Rank Fatalis, look at them as very old specimen, that can unleash their true power unlicke the "younger" ones.