As part of the questline to create an unbreakable rope, you will need to obtain two items. You should already have obtained the cat’s footfall from the first riddle. Now you will need to solve the Taking Root quest riddle which asks you to obtain the root of a mountain..how the hell do you do this!?
Cradled in rock,
At Asgard’s highest height,
A seed sleeps in Ymir’s cold grip.
Warm it awake, bring it to water.
For old bone to sprout new life.
Finding Asgard’s Highest Height
This one is quite easy, there are a few mountains but one of them is quite clearly the biggest. You should be able to fast travel to the central tower in Asgard. This is a very high point and will let you easily see the tallest mountain. You will see it to the East.
Warming It Awake – Activating The Seed
The seed is pretty easy to find as it is the only flat area at the top of the mountain. You will see there is some hay nearby. Equip your torch and set the hay on fire. This will satisfy the warm it awake part of the riddle.
Look over the ledge and you will see some water below. Pick up the seed and throw it into the water below. Jump down and collect the root of a mountain to complete the quest.