AEW has added a huge seven-team championship match to All In: London, and one mystery team is still waiting to be revealed.

Tony Khan confirmed that “Hangman” Adam Page, Brody King and Bandido will defend the AEW World Trios Championship in a Trios Roulette Royale during the Buy-In pre-show this Sunday.

The match originally started as an open challenge from Page, with Swerve Strickland among those responding. AEW has now dramatically expanded those plans.

Speaking during the All In pre-event media call, Khan explained that the match will work differently from AEW's Casino Gauntlet format.

“A Trios Roulette Royale. It’s a very different match from a Casino Gauntlet with one sudden-death pin. You’ll have trios entering until one trio or the members of one trio remain,” Khan said.

Six Teams Confirmed, But One Mystery Spot Remains

The champions will face a packed field featuring Bang Bang Gang, The Dogs, The Demand, The Death Riders and The Conglomeration.

That accounts for six of the seven teams, including Page, King and Bandido, but Khan revealed that the final position will be filled by a wildcard trio.

Khan suggested he has been working behind the scenes to secure something special for the remaining spot.

“I’m always out there scouting, talking in the world of wrestling, and these are developing situations. But I think I could feel a pretty interesting wildcard team in the seventh spot. So that’s what we’re going to do.”

Khan added that he was still working on putting the team together following Wednesday night's show.

“I have been working on this, and I still am working on this to bring in a great wildcard team. I think I’ll be able to get it done, and you have a guarantee that we’ll be starting this thing out for free on the Buy In.”

The mystery has naturally fuelled speculation ahead of All In.

Kofi Kingston and Xavier Woods have been heavily discussed by wrestling fans as possible surprise arrivals in AEW. With Swerve Strickland previously responding to Page's open challenge, some fans may now wonder whether the former New Day members could potentially join Swerve as the wildcard trio.

There has been no confirmation that Kingston or Woods will appear in the match, however, meaning the identity of the seventh team remains a mystery heading into All In: London.