Guilds of London: The Secret Guild of Guildsmen

Promo card included in The Cousins' War. Acts as another guild. "At the start of the game, put this card into play next to the guild tiles. Liverymen can be moved onto this card like a regular guild. When it resolves, the winner of this guild gets to take 1 of their liverymen that was on this card and place it [as a master] on an existing guild tile controlled by any player; then flip this card over (do not place a liveryman on it once flipped - i.e. it is not itself controlled by a master)."