The Magic Forest quest where you have to find someone or do something in the Land of the Dead leads to a headstone back in Magic Forest. When you click it it says quest completed but I don't think you get anything for it.
Basically, there are no time limits for quests in this game, so if you don't know where to go you will figure it out in the course of exploring the whole game. I love to do EVERYTHING in a game, all quests, all creatures killed, so everything gets done in the end.
Except for that in my first game I couldn't complete the 'find a Cyclops' quest because there were NONE for sale ANYWHERE in the game. Believe me, I checked.