One of the many Favors of God of War Ragnarok involves Ratatoskr and he will ask you to solve A Deer for All Seasons, to unlock this side mission you must have completed another Favor, the one "For Vanaheim". The reward for completing this Boon will be 4500 experience points for Kratos, 1125 for Atreus, 75 Slabs of Laments, Rond of Interruption and the Pure of Heart trophy.
- Talk to Ratatoskr
- Find the objects
- Return the Deer to Ratatoskr
- Talk to Ratatoskr again
An all-weather deer is automatically started when you approach one of the four deer that are in the crater area in Vanaheim. Head to Sindri's house and talk to Ratatoskr. Get the items from Ratatoskr (Leaves of Yggdrasil). Now that you have the items, you'll need to find the four seasonal deer throughout the Vanaheim crater area.
Deer of Winter
It is located at Mystical Portal of the Enlarged Tower, beyond where you fight the red dragon. Remember, you need Ratatoskr's Yggdrasil leaves in Sindri's house to feed the deer.
It is found across the bridge in the Jungle, which will require the completion of a Boon: Return of a River to fill the river bed again and access it. After the water runs out, you can row the boat up to the Heavenly Altar to change the time of day - essential for changing some plants in the environment. Then dock the boat on the island where the orcs are throwing stones, then defeat them. Later you can clear the path with your Blades of Chaos and swing towards the deer. You can't swing at night, it must be during the day.
It is located right next to the mystical entrance of the entrance of the Gorgo.
Deer of Spring
Found within the Wishing Well, accessible via Il Gorgo or La Giunga. The silver trophy, Pure of Heart is unlocked immediately after interacting with the 4th Stag, before returning to Ratatoskr to complete the quest.
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