Chibi Syrup

From the Super Mario Wiki

Chibi Syrup is an item in Mario Kart Arcade GP 2. It is one of Mametchi's five special items. The Chibi Syrup is a lock-on item, much like the Basin. Upon hitting a racer, the Chibi Syrup causes the racer to lose speed and shrink, as if they had been hit by Lightning. Eventually, the effects of the Chibi Syrup wear off.