The Order of the One Light is a Mission in Dark Alliance. The Order of the One Light becomes available once you complete all three acts of Companions of Icewind Dale. Missions in Dark Alliance need to be completed in order to progress the story forward. You can obtain more and better loot as you complete more Missions.
Missions in Dark Alliance are divided into three different Acts. Once you complete an act, the next one becomes available. When you complete all three acts, another Mission becomes available.
The Order of the One Light
Mission Briefing
Cultists that worship the Crystal Shard like a god have found Kessell's body and infused it with arcane power, reanimating him. Now he seeks to rebuild his army and take his revenge on Icewind Dale.
Preferred Gear Set Drop
♦ Keeper of Secrets Set (Bruenor Battlehammer)
♦ Alustriel's Gift Set (Catti-Brie)
♦ Wearer of the Mask Set (Drizzt Do'Urden)
♦ Captive of the Abyss Set (Wulfgar)
Unlocks
Once you complete all three acts of The Order of the One Light you unlock the following Missions:
- The Mask of Kelvin (You also have to complete Verbeeg Jamboree and The Goblin's Shard)
The Order of the One Light Acts

An Infernal Dispute
The Order of the One Light, they called themselves - cultists who worshipped the Crystal Shard like a god.
We found the Order's fortress - hidden within the Spine of the World. They were under siege by the forces of Levistus and had erected a magical barrier to keep the devils at bay.
We would have to recover the Netherese Keystones to bring down that barrier before we could enter the fortress and deal with the mages within.

Order of the One Light
Crystal Cult necromancers had reanimated the corpse of Akar Kessell and granted him arcane powers he never achieved in life.
From the safety of the warded inner sanctum of their fortress, he called out to any ally that would assist his rise to power once again.
We would need to break down the sanctum's defenses before we could deal with Kessell himself, hopefully, for the last time.

Return of the Tyrant
Kessell did not have the Shard to help him dominate creatures, but the power the cultists had given him was still dangerous.
Though few had answered Kessell's call, in time, they would grow and be a threat to the entire Dale.
Now was the time to deal with Kessell once and for all.