Steelix is a dual-type Steel and Ground Pokémon introduced in Generation II. It evolves from Onix when traded while holding a Metal Coat. Known for its impressive defense and formidable physical attack, Steelix is often depicted as a massive, serpentine creature made of steel. Steelix has a unique ability called Sturdy, which prevents it from being knocked out in one hit. Its design features a long, metallic body with large, jagged spikes, making it a formidable opponent in battles. Steelix is also known for its ability to burrow deep underground, allowing it to navigate through rocky terrains.