List of Giga Bowser's attacks:

Neutral A: Giga Slash
Neutral A + A: Bloody Claw
Forward Tilt: Dark Knuckle
Up Tilt: Heaven Scratch
Down Tilt: Earth Scratch
Dash Attack: Crushing Tank
Forward Smash: Fire Smash
Up Smash: Lightning Smash
Down Smash: Ice Smash
Neutral Air: Thunder Shell
Forward Air: Claw Smash
Up Air: Demon Horn
Back Air: Lightning Spikes
Down Air: Electric Brush
Grab Attack: Shocking Horns
Forward Throw: Death Cannon
Up Throw: Execution
Back Throw: Hell Toss
Down Throw: Diamond Crusher
Neutral B: Endless Flames
Forward B: Dragon Claw
Up B: Kaiten
Down B: Giga Bowser Bomb