Watt is a Li'l Sparky who had been held captive by the Big Lantern Ghost in Shy Guy's Toy Box. After the Lantern Ghost is defeated, Watt will join Mario and his party. In the field, Watt may be the least useful character, as she lights up the nearby area if it is dark. This can also be used to reveal hidden ? blocks
. In battle, Watt becomes much more useful as the electric attacks character. Her Electro Dash attack can pierce enemy defenses, making her perfect for heavily armored enemies.