When Wulfrik the Wanderer issues a challenge, your opponent cannot choose to refuse it. Furthermore, Wulfrik nominates which character will accept the challenge - your opponent does not get to choose as per the normal challenge rules.
Source: Warhammer Fantasy: 8th Edition
When Wulfrik the Wanderer issues a challenge, your opponent cannot choose to refuse it. Furthermore, Wulfrik nominates which character will accept the challenge - your opponent does not get to choose as per the normal challenge rules.