Onix resembles a giant snake with a large crest on its head and a body covored in a rocky surface. The Pokémon has a Sticky ooz that comes from the body that seems to gather rocks onto its body as it moves though its mountainy home, little is known why it has this ooz but many beleave its a defence, since young onix are born with soft delicet skin, the body secrests this ooz to colect rocks to serve as a plated outer covoring. Onix can be found in mountains and caves. they eat smaller mountain creatures.
Onix have large crests on their heads. in males the crests are much more larger than the females and the males use them in territory battles or battles for mates.