Enter the ROOM WITH THE SWITCH ON THE BLOCK and don't pull the switch to release the 2 mutants.
Instead go directly into the small room on the right with the 2 switches and the small pool.
Use only the switch on the right (when facing the pool).
This opens one of the gold doors outside in the OPEN AREA WITH THE TOWER AND HONEYCOMB STRUCTURE.
Swim down to the bottom of the pool, picking up 2 boxes of shotgun ammo on the way if you like.
Use the lever...
...to open the gold door in the room above.
Climb out of the water on the lowest step. Then climb the stairs and go through the gold door to emerge back in the OPEN AREA near the start. Pick up the walkthrough at the section "THROUGH THE GOLD DOORS."
DARK MODE: Even with brightness adjusted, dark images on a light background can be hard to see. May I suggest a reputable dark mode browser extension, such as Dark Reader? (Download only from trusted sites, like darkreader.org or your browser's web store.)
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