In God of War Ragnarok, you can obtain the Spirit of Rebellion favor by speaking with Durlin at Nidavellir after completing the Forging Destiny main quest.
Retrieve the hammer
Travel to the Alberich Hollow which is east of Dragon Beach. Interact with the device on the bridge to make the word appear. Head on over to the hammer and interact with it to cause it to raise. Loot the chest to receive the Hammer of the Revolution.
Return to Durlin
Head back to Durlin in Nidavellir and speak with him to complete the favor.
Rewards
- Kratos XP 3000
- Freya XP 750
- Whispering Slab x30
- Mountain Splitter