Steelix

Steelix (Japanese: ハガネール Haganeil) is a dual-type Steel/Ground Pokémon introduced in Generation II. It evolves from Onix when traded while holding a Metal Coat. Steelix resembles a giant iron snake, with a body made up of gray rock-like sections, three of which have blunt gray spikes protruding from them. It has a massive head with square-shaped teeth, and its eyes are red. Male Steelix have two sets of ridges on their lower jaw, while females have one. Steelix is said to have a body harder than diamond and can burrow deep underground, even towards the Earth's core. It prefers to live in mountains and caves and is known to chew through boulders. Steelix can Mega Evolve into Mega Steelix, becoming longer, almost doubling in mass, and gaining additional features such as blue eyes and crystal-like spikes.