Onix

Red / Blue: As it grows, the stone portions of its body harden to become similar to a diamond, but colored black.

Yellow: Burrows at high speed in search of food. The tunnels it leaves are used as homes by DIGLETTs.

Gold / HeartGold: It twists and squirms through the ground. The thunderous roar of its tunneling echoes a long way.

Silver: It rapidly bores through the ground at 50 mph by squirming and twisting its mas­ sive, rugged body.

Crystal / Sword: As it digs through the ground, it absorbs many hard objects. This is what makes its body so solid.

Ruby / Sapphire: ONIX has a magnet in its brain. It acts as a compass so that this POKéMON does not lose direction while it is tunneling. As it grows older, its body becomes increasingly rounder and smoother.

Emerald: There is a magnet in its brain that prevents an ONIX from losing direction while tunneling. As it grows older, its body becomes steadily rounder and smoother.

FireRed / Y: It usually lives underground. It searches for food while boring its way through the ground at 50 miles per hour.

LeafGreen: As it grows, the stone portions of its body harden to become similar to black-colored diamonds.

Diamond: When it travels underground, it causes rumbling and tremors. It can move at 50 mph.

Pearl: It squirms through the ground using its long and rugged body. It always eats while burrowing.

Platinum +2: It burrows through the ground at a speed of 50 mph while feeding on large boulders.

SoulSilver / Shield: It rapidly bores through the ground at 50 mph by squirming and twisting its massive, rugged body.

Black 2 / White 2: Opening its large mouth, it ingests massive amounts of soil and creates long tunnels.

X +2: Burrows at high speed in search of food. The tunnels it leaves are used as homes by Diglett.

Omega Ruby / Alpha Sapphire: Onix has a magnet in its brain. It acts as a compass so that this Pokémon does not lose direction while it is tunneling. As it grows older, its body becomes increasingly rounder and smoother.

Legends: Arceus: This chain of immense stones resembles a giant serpent. Tremors shake the earth above as it burrows deep beneath the ground, feeding on boulders as it goes.