The AC Valhalla World Event you can trigger by finding the first one is named Noble Harts; and it is very easy to complete.
So, below we will approach the Asgard’s Stags or the harts which according to the poem Grímnismál, eat among the branches of the World Tree Yggdrasill.
Before we begin, again, if this event doesn’t appear on your map, consider advancing through the Asgard story-arc up to the point when you have to reach the Well of Urdr (Well-Traveled quest).
Where To Find Asgard’s Stags In AC Valhalla
Good, so as you can see on my map; the first stag is found on the southern island of Asgard.
Look for this event south-west of Indre Holm.
When you approach the location on my map above, you’ll most likely see a lot of enemies.
Ignore all of them, and approach Dain, the Lifeless One, which is the first stag you need to find.
How To Find All Stags (Harts)
Once you do that, Dain will start moving through the woods.
Your goal is pretty straightforward. Tail the stags.
You can even summon your mount if you want to move faster, but no matter what don’t lose the stag.
All enemies and wild beasts in this mission can be ignored.
Dain will lead you to Duneyrr the Unknowing.
Now, follow both of them and they will take you to Durathor.
Keep following the herd and you’ll find Dvalin.
Finally, the four harts will lead you to Eikthyrnir.
This is the last Assassin’s Creed Valhalla hart or stag you’ll have to find.
As a reward for finding Eikthyrnir and all other stags, you’ll see a chest spawning in front of you.
Make sure you open it because inside is one of Ymir’s Tear Stones; which means that if you have a missing wealth collectible in Asgard, this is the one.
Without finishing the Noble Harts event you won’t be able to complete the Asgard Offering Altar.
That’s how you find all Asgard’s Stags and finish the Assassin’s Creed Valhalla Noble Harts quest, but now you should focus on freeing Audumbla.