The crab-like vehicle special weapon in Splatoon 3 is called the Crab Tank.
The Crab Tank is a special weapon introduced in Splatoon 3. When activated, the player climbs into a heavily armored crab-shaped machine with powerful ranged attacks. Its design gives the weapon a distinctive appearance unlike returning specials such as the Inkjet or Tenta Missiles.
The Crab Tank can fire rapid shots and a stronger cannon attack, making it useful for controlling space and pressuring opponents. It also has a ball-like movement mode that helps the player reposition, although transforming does not make the user invulnerable. Like other specials, it requires the player to fill a special gauge by inking turf.
The other choices are also Splatoon weapons, but they are different specials: Reefslider is a shark-shaped ride, Tenta Missiles launches targeted missiles, and Inkjet gives the player a jet-powered hovering form. Only Crab Tank is the crab-like vehicle.