Board Thread:Questions and Answers/@comment-8864605-20140629153823/@comment-26066301-20150209042103

Actually I think the snake DNA in question came from a horned viper, and an albino one at that. If you guys missed it, she has horns above her eyes that protrudes backwards. A viper is also venomous, just like Karai's mutant form.

I know that some will argue that the snake in the cage didn't have horns, but some snakes of this species can actually be born without horns at all. The reason Karai may have horns is because the mutagen may have tampered with the snake DNA and that is why she has horns when the snake in the cage doesn't.