Vancer was a god worshipped in the past of the northern continent who was named in The White Rose. Vancer is mentioned in the context of the TelleKurre documents from the Domination-era which several individuals were reading in the vain hope of finding the true name of the Dominator.
One of Vancer's priests was called "Erin NoFather", a mysterious man from the town of Slinger in the kingdom of Vye. Erin was the second husband of Ardath Senjak, a daughter of Baron Senjak and the sister of the Lady whose identity Lady usurped or swapped, protecting her true name from the Dominator, Bomanz, and countless others. Erin may have become the Dominator.
No characteristics or details about Vancer or his cult are supplied. Vancer is notable because so few northern deities are mentioned even in passing.
There is no indication in the Annals that Vancer was anything other than a mythological character.