Wilbur

Wilbur is a Beast monster boss that is always fought together with the Swine Prince in the Warrens.

Behaviour
During battle, Wilbur will use the attacks End This One or End These Two on one or two of your heroes. This marks your heroes for extra damage from the Swine Prince's attacks, as well as targets your specific heroes to the Swine King's attacks.

Wilbur can be killed to stop the marking of your heroes, however, this will result in the Swine Prince attacking all of your heroes every turn.

After the Swine Prince is defeated, the heroes will also have to defeat Wilbur (running however after the prince has fallen but before Wilbur has been defeated will still result in the quest being completed.) Wilbur will use Squeal, which does one to two points of damage, but mainly inflicts stress damage on your heroes.

Trivia
Wilbur's name is reference to Charlotte's Web, where the main character is a pig of the same name.

It is also highly likely that Wilbur is inspired by Wilbur Whateley from H.P. Lovecraft's story the Dunwich horror. Wilbur was the more "Human" of two brothers, sons of Yog-Sothoth. His sibling was the titular Dunwich horror, and he had the role of caring for the monster and keeping it contained until the time when it would be unleashed. When Wilbur is killed in the story, the monster goes on a rampage. This closely mirrors the relationship between the small, "normal" looking Wilbur, and the monstrous Swine Prince, as if Wilbur is harmed or killed, the Swine Prince will become far more dangerous and relentless in its attacks.