If the particle accelerator vent opens halfway and your partner cannot get through, the reported solution involves the cube and the weight pad. The player in the vent should put the cube onto the player who needs to stand on the pad, through the half-open doorway. Another player with the same problem confirmed that this suggestion helped.
This is a player-reported solution for the reunion point after the gravity section. It is not a verified layout, timed sequence, or guarantee that every half-open door has the same cause.
Match the room before trying the cube
Guide diagram: player-reported cooperation; positions and room geometry are not shown.
The report describes two separated Explorers trying to reunite. One player can grapple the vent open, but it stops halfway, leaving the other unable to crawl through. The missing step was not described as finding a second vent-opening button.
Before trying the suggested interaction, compare the roles with your partner: who is in the vent, who needs to stand on the weight pad, and whether the half-open doorway allows the cube interaction. If those details do not match your room, do not assume this is the same obstacle.
Coordinate the two roles
- Identify the player who is in the vent and the player who needs to use the weight pad.
- Discuss where the cube can be placed through the half-open doorway.
- Try having the player in the vent put the cube onto the other player as described in the report.
- Compare what changes around the pad and the opening before trying another action.
The account does not specify a keybind, a pixel-perfect position, a countdown, or a required character name. Do not add a sprint, jump, crouch, or timing requirement just because the opening looks narrow.
The diagram shows the relationship between the two roles and the cube. It deliberately does not show the room's geometry or the exact placement of the doorway and pad.
A partial opening is not proof of a bug
The original player believed the room was completely stuck, then recognized the cube interaction after it was explained. That makes this a useful puzzle check before restarting the session.
A vent that opens only halfway can therefore be consistent with the reported cooperation step still being unfinished. It does not prove that your grappling action failed or that the game expects you to force your character through the gap.
If the relevant interaction is unavailable even after you and your partner have matched the roles, distinguish that from simply not knowing the next action. For an actual softlock, checkpoint recovery is available through the main menu, with the host manually selecting the last checkpoint. Reloading is general recovery guidance, not a confirmed substitute for the cube step.