Giga Mac
Giga Mac is a giant, monstrous version of Little Mac first appearing in the multiplayer mode in Punch-Out!! for the Wii. He also appears as Little Mac's Final Smash in Super Smash Bros. for Nintendo 3DS / Wii U. Like Giga Bowser, Giga Mac's attacks are more powerful and have greater range, with some of his attacks being able to potentially make one-hit KOs when fully charged. The Straight Lunge also charges at a much faster rate.
Along with the power boost, Giga Mac also moves faster, and does not flinch from taking damage. However, he does not have a Power Meter, and his aerial attacks are still very weak. Additionally, the length of time spent as Giga Mac is shortened if he takes damage.
Giga Mac is unaffected by Metal Boxes, as he never gains a metallic appearance, even in a Metal Special Smash. He's also unaffected by Super Mushrooms, Poison Mushrooms, and Lightning, but his size can be altered by playing a Giant or Tiny Special Smash.