The delightfully aggressive Make My Head Grow is a prime instance. It's a two-player spirited flash game where the objective is to push the opponent's box over the border of the platform. Employing the arrow keys for player one and the number pad for player two, you can slam your character's face into the ground to build his head grow. Bulge can be fun! Once your head is overstated enough, you can build up momentum and slam face-first into the inner wall to give the necessary momentum to slither your box into the opponent's. There's a great mixture of plan and luck involved, as you can easily slam your face into the floor one too many times and create your head explode, giving your opponent a few seconds of benefit as you convalesce.