|| This teeny-tiny article needs some work. You can help Sonic Retro by expanding it.
Prison Hall is the fourth stage of Sonic Forces and the second to be played with the Avatar. The stage is a re-imagining of Death Egg Zone from Sonic & Knuckles, which has been rebuilt and re-purposed into a space prison for the resisters captured by the Eggman Empire, including Sonic the Hedgehog.
In terms of plot, in a flashback in the City, Infinite attacks some resisters, eliminating all of them except the Avatar, who with fear tries to attack him without success. Returning to the present, Rouge is revealed to be the spy commanded by Knuckles and then informs to other members of the Resistance that Sonic has been trapped for months in a space prison onboard the Death Egg which, to the surprise and awe of all, has been rebuilt. The Doctor plans to banish Sonic into space soon, so they have to act fast.
Thanks to having stolen a shuttle from the Spaceport, the Resistance plus the Avatar infiltrate the Death Egg for a prison break. However, their arrival puts the location under high alert (with Espio sensing Sonic's close proximity), and the majority of the rescue team is forced to deal with enemies, with only the Avatar making it past them and through the best route into the internment facility where Sonic is.