If you only have mend (harm/negate combined) and you can't heal, the game stops you from playing since you can't do anything
Viewing post in The Tree That Touched The Moon comments
That's a cood catch. I mean, I want discovering different spell fusions to be part of the learning curve of the game, and I was aware sometimes you may end up without attack spells (that's why I included explosive shards & wands in the game, but again, you don't always have these), but I see this can be annoying. For now, I can unfortunately only recommend restarting the game, but I'll adress this in the next update - I'll probably make it so that if you're ever without an attack spell, you immediately get an event which gives you one of the basic ones.