Great idea, and fun game. The control took long to get used to. Maybe adding the arrow key to move forward in addition to what you have? Found I was never using the dash forward, and just the jump button to clear obstacles (to avoid myself from being confused about which buttons to press by having one less button to think about).
Overall fun game. Wish there was a way to defeat that monster rushing the player to move forward, but also have a new one spawn in place of it. Maybe a bomb ( that never moves from its tile) that is triggered on attacking it, then detonates on auto-timer -- so player has to time the hit/explosion? Excellent work!