The Dink Network

Talked to the dolman (the big rock on top of a smaller one) in the Forest of Wickedness. Pressing spacebar (to talk) doesn't work. If you hit it, it says "You can't get blood from a stone". Maybe that's a clue or maybe I have to do something else/extra to get the invisibility spell/magic.

I knew from the walkthru that's what I had to do, but how did I know; who told me? to go talk to the dolman?

Any ideas folks? Thanks!

edit: got it. Balder is the key.