Members of the Order in Assassin's Creed Valhalla: Wrath of the Druids are referred to as the Children of Danu.
They are causing trouble all over Ireland, You'll encounter The Oak through the main story, but you will still need to kill the rest should you want the Gae Bolg legendary weapon.
Where to find The Oak
The Oak will be encountered at the end of the Wrath of the Druids DLC in Assassin's Creed Valhalla.
We won't spoil that for you here, so read on for the other Children of Danu.
The Wren
You can find the Wren at Rathcroghan's Feast in Connacht, south of Lough Gara. It's part of the main story, so you can't really miss it.
The Ash
The Ash will be found to the northwest of Lough Gara, at the mines in Kesh Corann.
The Cursed
Another of the Children that forms part of the main story, you shouldn't have any trouble locating The Cursed.
The Deer
The first clue to finding The Deer comes from defeating The Cursed. You'll find it on the northern shore of Ulster Lake.
The Blaze
The Ash will give you the first clue to finding The Blaze, which can be found burning houses between Black Pig's Dyke and Clogher.
The Mist
You'll find the first clue to finding The Mist following your encounter with The Blaze. It can be found on the northwestern shore of Northern Ireland.
The Whisper
Following on from The Mist, head to the swamps east of Inchroe to find The Whisper.
The Spider
Once again, The Ash provides the first clue to the location of The Spider. You'll find her in Dublin.
The Seed
The Seed forms part of the main story, but it's inaccessible until late on. When the time comes, you'll find them at the fortress at Dunseverick.
Why should you complete the Children of Danu quest?
Quite simply, while killing all of the Children of Danu will help Ireland's cause, it will also reward you with the legendary spear Gae Bolg.
The Children of Danu will also drop valuable runes, as well as granting a significant amount of experience per kill.
