If you're going for the achievement/trophy, you'll want to start the level as usual. Skip the first secret and head straight for the open area with the tower. Kill or run past the first mutant. Kill or ignore the 2 flying mutants. Then proceed as described here:
You are ultimately headed for the uppermost square opening in the honeycomb structure below.
Begin by turning around so the open area is behind Lara. Then jump over to the ledge on the right side of the tower.
Walk to the edge of the opening. Then jump onto the sloping stone wall that runs along the entire north side of this huge cavern. Slide back and grab the edge.
Now traverse along the wall to the right.
After you pass the area with the glowing patches, the top of the wall slopes upward a bit then levels off. Stop in the middle of the first level block.
You can't see it, but the uppermost opening in the honeycomb structure is now directly behind Lara. (You can save the game while hanging, use Photo Mode to check that Lara is in the right spot, then reload. Just be sure to hold Action while the game loads, so she's still hanging when the game starts.)
Pull up onto the sloping top of the wall and quickly press Jump to backflip off the slope and land on the honeycomb.
Lara will then slide into the hole and fall a long way, eventually landing in the pool deep inside the pyramid. Resume the walkthrough at the final section, "INSIDE THE PYRAMID (LOWER LEVEL WITH POOL)."
NOTE: If you use this shortcut and finish the level in under 5 minutes, you'll unlock the "Emergency Escape" achievement/trophy.
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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