The Solo Rules and the card The Guild of Solo Boardgamers were originally available at Essen 2016.
Guild of Guildsmen
The Guild of Guildsmen is available in the game The Cousins' War.
At the start of the game all players can agree to play with the Secret Guild of Guildsmen promo card. If they do, place the card face up to one side of the play area. This card acts similarly to a guild tile, but is not part of the array of tiles. Place a 2nd place reward token on the card in the indicated space. Players may move liverymen to and from the card as if it was a regular guild tile, and it is resolved in the same way during guild resolution after all other guilds have been resolved.
1st place reward: 2 VPs. Move 1 of your liverymen from any guild, special building tile or the Guildhall to any resolved guild (occupied or not); that guild counts as yours for game end scoring and for adjacency, as well as for the owner of any existing master on that guild. When resolved, turn the card over, but do not place a master on it; the Secret Guild of Guildsmen has no master.
2nd place reward: Token + neutral liveryman.