Fun game! I really like the core mechanic. Like, I /really/ like the core mechanic. This type of game is one of my favorite things to play - there's just something so satisfying about ramming through goblins and jumping over spikes in a cool mine cart, haha!
It was kind of frustrating that bumping my back into the wall damaged me instead of just /not/ letting me back up - I killed myself probably 20 times backing into walls because my brain just could not compute the idea that it would hurt me, lol.
Also, the projectiles knocking you out of jumps really feels weird - I thought I'd be able to jump over the projectiles, but I got knocked out of a jump into bouncing off of spikes into the wizard's body for the 3 damage insta-kill quite often.
Also, having the music fade out then fade back in on death would be a nice little Quality of Life feature, since now it's just a hard cut.
I was super happy that you generously restarted me at the start of the level I died on, instead of needing to restart the game. That kept me /super/ engaged. I probably would have given up a lot sooner if I had to completely start over every time, haha!
Overall, I had a LOT of fun playing this. Really excellent work!