While we thought it was over, the Immu's Rooms, or rather the Kawa's Rooms, made a comeback starting with cycle 4.5.X. Immudelki added a new secret code in the game. Once entered in the terminal it started a riddle to find an hidden room in the factory. To have the riddle being shown in cycles 4.5.X and 4.6.X, you need to have the Kawabata holoviz entry to be unlocked by destroying 3 replikas in a single game session.

Players had to look around the different rooms of the factory to find glitches, like what was done during the Kawa's Room of cycle 4.0.X. The first 3 glitches necessary to open the room are in the scanners room, in the cathedral (behind the elevator) and in the boiler room. Once those 3 glitches found, a last should activate when going in the center of the boiler room, with a new opened pathway to the hidden room.

The 'Boiler Room 2957' contained tags on the walls, spoiler chests, old items which made an appearance in previous Immu's Rooms or anniversary trailers, as well as notes about important elements of the story mode. On the desk was a computer screen showing the laboratory and a folder with notes from Kawabata himself. He explains the different points of his investigation on the story mode and how he came to create this room. A lever located on the desk activates a system which elevates the holomap in the laboratory, revealing a sticky note written by the kankrelat for the player.

Made like an ARG (Alternate Reality Game), Immudelki discreetly announced this new Room with a shot in the trailer of IFSCL 13th anniversary, then with a promotionnal picture for the release of the last patch for version 4.5.6. Lastly, multiple shots of the room where also showed in the 4.6.X trailer. Only then, Immudelki decided to officialy reveal this Kawa's Room with a dedicated announcement video.