There's a lot of potential here, but I found the grapple mechanic super hard to get right, and the enemies are very unforgiving. I got two good swings in a row once, but most of the time I failed horribly. I felt like it might be easier if the player had lots of momentum so you could focus just on the swing and not also on pressing the right direction as you go around the corner.
The pixel art and music are solid. Nice work.