681 Prey Support
Background Information: Using the latest version of Prey: Mooncrash on the date of this post. Hardware where the bug was noticed was an original PlayStation 4.
Description (Some information may be extraneous): Corruption level 5, using the Security Officer character. Took place in Moonworks in the room that always has an active turret in it and another on a workbench. The room also features a destroyed catwalk leading out of it. From the door leading to the destroyed section of catwalk I threw two Typhon Spores at enemies below. From an unknown location a poltergeist used their weapon grabbing attack moments after the Typhon Spore was thrown, before another weapon was selected. The animation was typical, except there was no Typhon Spore in the player's hand, though the hand still looked like it was holding an invisible Typhon Spore. I attempted to resist the grab by reflex, though I don't know whether I was successful or not, either way I did not notice any weapon being tossed on the ground. After the animation completed I attempted to move, but could not. I hit the Triangle button and the weapon switched to the Stun Gun, which presumably was the last weapon I used. However I was not able to do any other action than reload the weapon. I could not look around or jump or move or even open the transcribe, though I was able to open the menu, where the Save and Exit option was greyed out. Eventually the Poltergeist used it's lift ability to push me in the air, after which I was able to look and move again. I could switch weapons, but could not fire. I did not test whether psi abilities still worked or if opening the transcribe worked.
Steps for Reproduction: Presumably this will work with any thrown weapon, though it has only been observed using the Typhon Spore. Throw the weapon. In the time between the weapon being released from the player into the environment and the weapon being switched to another (possibly during the throwing animation, though the Typhon Spore was definitely thrown) have a poltergeist use it's weapon grabbing attack on the player.
Notes: The timing is likely pretty exact, which explains how this has not already been found and fixed. The frame of opportunity may be milliseconds long in between some sort of state switch for the Player Controller. Testing this would not be easy, though I'm not familiar with the Codebase nor the tools available to testers. Since this bug effectively ruined a playthrough I would say that the severity is high.
Workarounds: None known, waiting to be attacked again did not entirely fix the problem.