I was under the impression that all dead ends had been eliminated from this version of King's Quest III. So I took my time with the visits to town during Manannan's absence. I gave him all the food I had when he returned (apart from the porridge, I remember I have to cast a spell on it first), and after that I just ignored him as I thought all he'd do would be to send me to my room. However, apparently you can only fail to feed him four times, as he now kills me. Now that I have no more food to give to him, is it a dead end?
Spoiler
Have you made the magic cookie yet?
I have not. But I just found out that -unlike in the original- you can get another bowl of porridge from the bears' house, so there's no dead end. Thank you anyway!