Giga Bowser is the final smash of Bowser so strictly speaking yes.
No.
No,Bowser Jr is not in brawl but the original bowser is.
Bowser comes unlocked
NO.
Bowser
You can't.
The only way to play as Giga Bowser is to use Bowser's final smash in Super Smash Bros Brawl.
No hes not
No, or at least not by hack.
super Mario bros DS, super smash bros. brawl, and Mario kart wii
Super Smash Bros., Super Smash Bros. Melee, Super Smash Bros. Brawl, Super Smash Bros. for Nintendo 3DS/ Super Smash Bros. for Wii U, Super Smash Bros. Ultimate.
You can only install Super Smash Bros. Brawl on your Wii with a Super Smash Bros. Brawl disc.