Tomb Raider I-III Remastered Starring Lara Croft

After entering the large open area, head to the left side of the central structure (it might be easier to kill the Atlantean running around). From the path on left side of the structure, jump onto the sloped outer wall and grab the ledge. Shimmy along until you're in front of the fallen brown piece of structure with all the holes.

You may want to use photo mode to look in each of the holes to determine which one you need to be in front of. One of them had a long drop into water. Facing from the entry, I believe it's the top left.

Position Lara in front of the hole, climb up onto the sloped wall and instantly jump backwards to land on the brown structure and slide into the hole.

Lara will fall, screaming, into a pool of water. From there, climb out and pull the switch to finish the level in less than 3 minutes

Good luck!

Tomb Raider Unfinished Business - Atlantean Stronghold (Level 1)

There is a method to skip almost the entirety of this level. From the start, drop down the hole ahead, wait for the boulder in the next hallway then head into the open area. Fight or simply run past the enemies and go to the left side of the large tower structure. There is a long ledge going along the upper left side of the area that you can jump to and grab. Shimmy all the way over and line up with the hole in the golden structure behind you - use photo mode to help. Then climb up onto the ledge and do a backflip into the whole, save/reload in case you miss.

Once you drop to the bottom, climb out and find the exit hallway with a switch to end the level - can be done in under 2 minutes.

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