Thanks! And yeah, a good chunk of feedback hinted that I find a way to label/remind players of the elemental keys, so that's what I'm working on implementing for an update.
I tried to accommodate by having the overall session be short (60 seconds), but outside of the game jam and building on the prototype, I think I could consider making stages/incremental introduction to elements and spells or adding/reducing difficulty.
Thank you for giving my game a go, and your feedback! Sorry I'm so late giving a response!