Interesting concept!
One thing I liked was the feeling of relief when I encounter a group of goblins, essentially acting as a health pack in a time of need. Were one of you inspired by Ultrakill by chance?
The one problem I keep on encountering is how powerless I am against ranged weapons. I could use the missile, but it costs mana, and I have so little mana at the start that I am forced a bombardment of arrows. The player feels powerless in that way, which deson't fit the feel of the game. That's just a small nitpick though.
The story was quite interesting as well.
Overall, very cool ;)