-Feels a annoying having to select, change, then select again for the options menu. Due to it being so simple, I'd rather just press left and right to change it immediately. Furthermore, the lack of input echoing is noticeable.
-Looks and sounds nice. Seems like your standard platformer, simple but well done theme. It took me awhile to realize how the charge attack worked, because I didn't hear the sound denoting a full charge. Maybe also change the blinking color to better communicate?
-Feels unexpected to walk down slopes at double speed.
-Beat level 1. I liked the variety of enemies.
-If you stop while walking uphill(45* I tried on), the character does a little hop.
-Beat level 2, and final level I guess. The hardest enemy to counter was the snail, since I was bad at its timing. The biggest flaw visually is the use of what seems to be some iffy collider. It caused sliding off a ledge instead of just walking off, and the hopping when stopping on a upward slope.
Was a fun demo, keep at it.