Your roving eye misses nothing. Intrigued by the red flame as you are, you see something glimmer in your peripheral - and there, embedded in the face of a large boulder to your right, is the broken outline of a Rune that seems to have been roughly shoved into place. How did it end up there?
No matter.
If you're dextrous enough, you could probably pry it free with your claws and a little bit of help from a friend.