×It might be possible to do it with the same method as the room to the north, wrapping the gentryii around a stalwart/wraithwing instead of a mirror, but I didn't do that.

×Brained gentryii don't go for stalwarts (although they'll run over them if they're in the way.)

×Unbrained gentryii will go for the stalwart though (if the stalwart is closer)

×You want to position a stalwart south of the gentryii plate. Then you can just wrap the chained gentryii back up and stand in the middle.

×I killed one stalwart and one wraithwing so that the remaining wraithwing gets released first. You'll want the wraithwing in one of the three columns underneath the gentryii plate with yourself to the south, so that when the stalwart gets close the WW will flee to the north. Which column depends upon how the stalwart approaches though, which is subject to stalwart randomness, so checkpointing/undoing to make adjustments will undoubtedly be necessary. If the stalwart approaches from the east it might avoid some of the randomness, but I think I always had him approaching from the south, so I don't know if that can be set up.