Withdraw

Withdraw (, Withdraw into Shell) is Squirtle's side special move.

Overview
Squirtle retreats inside its shell and speeds across the stage, powered by a jet of water shooting out the back of its shell. During this attack, Squirtle's shell behaves like a Green Shell for a limited amount of time. Squirtle cannot take damage from most attacks during Withdraw.

Squirtle is unable to change direction on its own. Spinning up and down hills can alter the speed in which the withdrawn Squirtle will move. The attack can be cancelled if the control stick is moved in the opposite direction that Squirtle is moving. The invincibility provided by the move is sufficient to block many attacks and even Final Smashes that do not involve grabs. For example, Marth's Critical Hit can be negated, but not Ike's Great Aether.

Like some other moves, Withdraw's speed can be altered by smashing the control stick, instead of just tilting it. If another player lands on Squirtle while it is performing Withdraw on the ground, Squirtle enters a unique stunned state where it is flipped on its back momentarily. If Squirtle is footstooled while Withdrawing in the air, then the move will be canceled and Squirtle will be put into a helpless state of free fall and be unable to recover until it lands on the ground or grabs a ledge.

Origin
Withdraw is a Water-type non-damaging move introduced in Generation I from the Pokémon series. The move is only capable of being learned by Pokémon with shells. In battle, the move increases the user's defense by one stage. However, as Withdraw is not an offensive move, Withdraw's usage in Brawl may be based on Squirtle's use of Rapid Spin in the Pokémon anime. Squirtle learns Withdraw at level 28 in Generation I and at level 10 in Generation II and onwards.

The footstool mechanic is likely an allusion to Koopa Troopas from the Mario series, where they would retreat into their shells and remain vulnerable when stomped on by Mario. The way Squirtle struggles to get up is similar to real life turtles when flipped over their backs.

Trivia

 * When Squirtle knocks into another character while using Withdraw, it makes the same sound as a Green Shell.
 * If Squirtle gets hit with a Pitfall item, or an attack that acts like a Pitfall item while staying on the ground, Squirtle will still be buried, but will take no damage.
 * If Squirtle gets hit with an attack that involves acting like hitstun, Squirtle will still get hitstunned, but will take no damage.
 * If Squirtle is hit by Ice Shot, it will take damage, hitstun, and return to its normal mode.
 * If Squirtle is hit by Thwack while performing Withdraw, it will be Instant KO'ed, but it will not trigger the Special Zoom.