Steel is a strong material, but in the context of Pokemon, Steel-type Pokemon have weaknesses to certain types of attacks. Here are the main weaknesses of Steel-type Pokemon:

• Fire-type moves: Fire-type moves are super effective against Steel-type Pokemon, meaning they deal double damage.

• Fighting-type moves: Fighting-type moves are also super effective against Steel-type Pokemon.

• Ground-type moves: Ground-type moves are super effective against Steel-type Pokemon as well.

Its worth noting that Steel-type Pokemon are also resistant to certain types of moves, including Normal, Flying, Rock, Bug, Grass, Psychic, Ice, Dragon, and Fairy-type moves. Additionally, pure Steel-type Pokemon are immune to Poison-type moves.

In summary, Steel-type Pokemon are weak to Fire, Fighting, and Ground-type moves, but they have resistances to several other types of moves.