I made this game for the Game Maker's Toolkit Game Jam.
The theme was Downwell's Dual Purpose Design. In this game you can only move by dive kicking. I ran out of time to implement enemies, but the dual purpose would be attack and movement. The dive kick button is the same as the jump button as well.
Press Left or Right to face left or right on the ground. Press either of the X or O buttons (Z, X on keyboard) to Jump from the ground. While in the air, press the same button to dive kick.
Thanks to @MBoffin on the pico8 BBS and twitter for the use of the code for the camera movement!