Re: Fairy Tale Challenges?
Wow! Korvar, great ideas!
But in my campaign these feats are up to gods not heroes. I would go for a mixture between known places or artefacts and new story arcs.
1- The heroes arrive at asgard via the bifrost bridge, where they meet the guardian of Asgard Heimdall. Heimdall greets them in a friendly manner, because he can see and hear far and has heard of their heroic deeds. Heimdall assigns them a quest. His horn, the Gjallarhorn has been stolen, and the heroes must retrieve it. If the Gjallarhorn is blown, it will announce the end of the world, Ragnarok. He gives the heroes his horse Gulltopr, who will carry them to Jotunheim to steal back the horn.
2- In Asgard the heroes will find the garden of Idun, the goddess who grows the apples, that give the gods their immortality. Her garden is a mess, because Tanngrisnir and Tanngnjost, the goats of Thor, have completely wrecked it. Now Idun asks the heroes for help. Capture the goats, but do not harm them in any way. Otherwise their owner, who happens to have a bad temper, will be quite upset. And by the way, what happens if one of your heroes gets hungry and tries one of those delicious apples?
3- Arriving at Valhalla, Odin assigns them their third quest. The dead warriors in Valhalla drink milk from the goat Heidrun, standing on the roof of walhalla. Heidrun has an infection and her milk has become undrinkable. Now it's up to the heroes to cure the goat. Perhaps a herb from the realm of the dark elves will help, or a scale from the Midgard Serpent, or drop of dew from Nifflheim? Think of something scary and extremely dangerous!
That should be a trip your heroes will not forget for a long time.