Metal Mario (character)

Metal Mario is a powered up metal version of Mario who first appeared in Super Mario 64, he is virtually invincible and can only be hurt by long falls.

Super Mario 64 / Super Mario 64 DS
When Mario uses a Metal Cap in Super Mario 64, he becomes Metal Mario, a living embodiment of metal. In this from, Mario is invincible and can destroy enemies just by running into them. Metal Mario is also very heavy, and as such, can withstand strong winds, underwater currents, and can walk on the bottom of bodies of water. In addition, he doesn't need to breath, meaning he can stay under water until the metal power runs out. However, Metal Mario is slower than the regular Mario and sinks in quicksand quicker.

In the Super Mario 64 DS version of the game, only Wario could turn into metal and will therefore become Metal Wario, and did this by using a Power Flower.

Mario Golf 64
Metal Mario is an unlockable playable character in Mario Golf 64.

Dr. Mario 64
He is also the final boss of Wario's storyline in Dr. Mario 64. In this game, Metal Mario can be unlocked as a playable character by beating the entire game without losing once.

Super Smash Bros.
In Super Smash Bros., Metal Mario is a stubborn mid-boss before the game's final boss, in the here and in the other Smash Bros. games he is far less powerful and is suseptible to much more than in Super Mario 64. He is a much more durable character than the regular Mario. In fact, only when Metal Mario's damage exceeds 180% can he be knocked down.

Super Smash Bros. Melee
He returned as a mid-boss in Super Smash Bros. Melee and as one of the game's many trophies. In this game, Metal Mario would occasionally fight alongside his brother, Metal Luigi.

Super Smash Bros. Brawl
The Metal Box item returns in Super Smash Bros. Brawl, and thus, allows Mario himself to turn into Metal Mario when he collects the item. This can also be used as a setting in the Special Brawl. However, despite his role as a boss in Super Smash Bros. and Melee, Metal Mario did not reprise this role in Brawl.

Mario Party 7
Metal Mario also appears in Mario Party 7 when Mario uses a Metal Shroom Orb on himself to avoid traps. As a matter of fact, all the partiers could use the Metal Shroom Orb to make themselves metallic.

Mario Strikers Charged Football
It appears that Mario can become Metal Mario in Mario Strikers Charged Football when he peforms his Mega Strike.

Trivia

 * In Super Smash Bros. Melee, near the place where the "M" logo would appear on his trophy is a view of the Yoshi's Island stage.
 * In an interview published in 1991 (in Nintendo Power's Mario Mania Player's Guide), Shigeru Miyamoto reportedly said: "Who knows what Mario will look like in the future? Maybe he'll wear metallic clothes!" Metal Mario then appeared in 1996.
 * In Mario Golf, Metal Mario's blue color change bears resemblence to Shadow Mario.
 * In the Super Smash Bros. series Metal Mario appears unable to speak.