Extra points:
Wait for a tank that enters the river during certain levels. Move your monster to the opposite side of the river and rapidly tap Punch to collect extra points when the tank leaves the water.
Regain energy and steal points:
Start a two player game. Eat the player that transforms into a human after losing all energy to gain their points..
Super jump:
When falling into water, press Up + B to jump off of the surface. This may be used to jump onto buildings.