I found myself a bit confused on how things worked mechanically. It's still not clear to me what the energy bar is for exactly, or how the throw attack works, exactly. It seems like there's some sort of cooldown on the throw attack, but I couldn't find any visual indication of what the cooldown was or when it was available to me. It was also difficult to tell when my melee attack was connecting and how much damage, if any, it was doing.
Another issue with the melee attack is that the delay between pressing the button vs the animation of swinging the sword is pretty big, but the actual hitbox of the attack is instantaneous. This means walking up to an enemy and pressing melee attack causes the enemy to just vanish, then half a second later you swing your sword, which is pretty confusing. Once I realized this was the case, I was able to win fairly quickly.
It also seems like you can spam the melee attack button to continually put out new attacks, much faster than the sound effects and animation make it appear.
The page description also says you can hold down either attack key to charge, but I never noticed any difference between holding a button vs tapping it.
I did also get stuck on the inside of a rising floor tile once.
On the other side, the pixel art looks great, and there's good variety in the enemies and their behaviors - I particularly like the smaller enemies that chase until they attach to you and detonate. They made me pay closer attention to watch out for them in a way that still felt fair