After using the switch to open the THIRD GOLD DOOR, turn so the switch is on Lara's right, walk to the edge, jump forward and grab the ledge ahead, then pull up.
Climb onto the next block (i.e., the one where the mutant was standing when you came in). Then turn about 45 degrees to the right and jump to the ledge in front of the gold door.
Take a running jump across the gap above the spike room onto the slightly sloped ledge below the block with the small medi pack. Climb up to get it, drop back down and then climb up into the opening on the left. Pick up the walkthrough at the section titled "ROOM WITH VAULTED CEILING AND HOLES IN THE FLOOR."
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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