Negative Zone is Luigi's Final Smash in Super Smash Bros. Generations. When Luigi gains a Smash Ball, Luigi will create a circled-zone with a Negative color. When someone goes in it, they'll either get damage, have a flower on their head, or will Taunt. Note that Luigi will be dancing in the beginning of the attack.
Nintendo Wii - Super Smash Bros. Brawl 2008