Chomp (ワリオかみつき Wario Kamitsuki Wario Bite) is Wario's neutral special move. When the special move button is pressed, Wario opens his mouth and bites forward. The bite itself is non-damaging, except against the Subspace Army; something has to go in Wario's open mouth for the move to have any effect. Another method he can do with this technique is to hold the special button and Wario will keep his mouth open for longer. This acts as a grab, and can hit shielding enemies. If the button is held down, his mouth stays open briefly, making it possible to grab anyone who moves into range. While grabbed, Wario can bite by pressing the special move button, dealing a small amount of damage each time. The higher the enemy's damage, the more times Wario can bite. This can also be used to block Snake's recovery instead of taking a bit of damage.
Chomp can also be used to eat items and projectiles, up to 3 if Wario is close enough. Wario can do nothing and simply swallows the projectile or item. Eating a large item, such as a Crate, takes longer to swallow and leaves Wario more vulnerable. If it's a status or recovery item like a Superspicy Curry or a Heart Container, Wario will immediately gain its effect. Explosive items like a Bob-omb are damaging to Wario, dealing 6% damage, but damaging anyone in blast range. Any object that can be picked up (Link/Snake's bombs/grenades, Peach's Turnips, Diddy Kong's Peanuts/Banana Peels, Waddle Dees/Doos etc.) can be eaten by Chomp. The three exceptions to this are Mr. Saturn, Poké Balls (as well as any holdable Pokémon inside), and the Smash Ball (which can't be picked up with a single button press).
This move seems to be inspired by one of Wario's abilities in Wario World, Hyper Suction, where he opens up his mouth and inhales to suck in coins. It doesn't allow him to eat up items or to chew up enemies like in Brawl, though. It is also inspired by a microgame from the original WarioWare where Wario has to chomp on a hotdog to win the game.
 See also
"Attack by chewing on opponents. You may also eat items this way."