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.
