Rules FAQ
- You can trigger Lord Steward even if attached character is not participating in the challenge.
Title.
Unique character only.
Attached character gains an icon and the Steward trait.
Reaction: After you win an challenge in which you control a participating Steward character, choose a character with printed cost X or lower controlled by the losing opponent. Take control of it until the end of the phase. X is the number of Steward characters you control. (Limit once per phase.)
Link: Decklists
Rules FAQ