The Warduke

Covered in armor, head to toe. Works hand in hand with Caeryn. It is unclear the dynamic between them.
He appeared to have taken over the body of Alexi- a friend of Estel and the original OsterRats. As such, it is only fitting that the Warduke, in the body of Alexi, was taken down by the OsterRats after a confrontation on the road, and again for a second time in the basement vault of the Gilded Throne.
On his body was an invitation to a meeting between the Warduke, Lady Ealma, Lord Kozco, Lord Broxlith, and Sir Talhymon in the First Elves ruin in Rat's Rest. The OsterRats attended in his stead.
It is not known if Alexi was the originating body of the Warduke, or if he had merely been possessed. However, after meeting his demise in the vault, the OsterRats picked up his various equipment- the Dread Helm, Flametongue Longsword, Adamantine Half Plate+1, and Battering Shield. When Estel peered into the depths of the helm, a force tried to overtake him, thwarted by his strength of will.
The Warduke's equipment was given to Sir Galdahar and were promptly destroyed. It is thought, but not confirmed, if this ended the Warduke's presense.