Success!

Definitely has potential if expanded upon.

Hit boxes on the spikes are also wider than they appear, which can be annoying especially after beating a section just to needlessly die on spikes when you didn't technically touch them.

Music also gets repetitive after a while and could simply use some more tracks with different sounds.

I also don't get how if you share taking damage with the other person, how they can just come up and stab you and nothing happens to them. Seems like a bit of a hole in the mechanic in my opinion, but the gameplay was still interesting and I did find it fun to play.

Hopefully you'd consider adding more depth to the game and making significantly more levels as I could see this being fun to play with a bit more meat on its bones.