Portal 2 Sixense Perceptual Pack
The Portal 2 which tried to put the Portal series into Virtual Reality, made for the Sixense Creative Senz3D hardware.was a DLC for
It came with 20 unique maps, under the prefix sp_a*_sx_. The similarly-named Portal 2 Sixense MotionPack DLC, which some of the aforementioned 20 maps are from, bundles along six extra Co-Op maps, with the prefix mp_coop_sx_.
The main feature of the Perceptual Pack was how it uses the Creative Senz3D hardware to create unique mechanics otherwise normally impossible, such as moving Portals on their side. Likewise, the Motionpack does this using the Razer Hydra hardware.
Both the Perceptual Pack and the MotionPack were published by Sixense. The MotionPack was released in 2011, and was obtained via Steam keys supplied with all Razer Hydra purchases, while the Perceptual Pack was released in 2013, and was free on the Steam store, before being delisted.
It was delisted from the store at 16 August 2022 UTC for an unknown reason, possibly it could be related to the camera (which was required to play the DLC without using mods) lacking drivers for the newer versions of Windows (such as Windows 10).