When Negative Zone is used, Luigi emits a strange force field that causes random status effects. The force field is fairly large as it can take up nearly all of Final Destination. Anyone else that is trapped in the Negative Zone will suffer a random status effect such as sleep, slowness, or confusion. The move itself lasts a little over 10 seconds and Luigi can move on his own after he finishes dancing. The Negative Zone isn't useful for direct KOs but it will leave any foe trapped inside wide open to an attack.
Negative Zone is the only Final Smash in the Super Smash Bros. series from the Mario series that doesn't return in the next game.