Medusa's Lair was a room in Olmec's temple. Medusa's Lair replaced The Heart Room, and becomes the first central room to require an objective to be completed to move on in the temple. In Medusa's Lair, a contestant must put a certain number of snakes into the Medusa head mounted on the front pillar. The room kept the old background from the Heart Room and was essentially identical in appearance to its predecessor except for the stone statue and several snakes coiled around the stone railing.

In the first eight episodes in Layout XI that featured Medusa's Lair, the contestants were required to put four snakes into holes in her "hair". However, starting from The Lucky Medallion of Atocha, the contestants only had to put two snakes into the head as four snakes were too much for the contestants. The snakes also had to be put into Medusa's head properly in order for the doors to be unlocked. Once the snakes were in properly, Medusa would let out a loud shriek and her LED eyes would always light up red.

Medusa's Lair had a fair share of debatable incidents, although it is not known if there were production errors or not. Typically, the head would let out a small scream once a snake was placed in, but in episodes such as The Missing Eye of David and The Silk Sash of Múlàn, the sound effect did not play, possibly confusing the contestants. As a result, Tony from The Stone Head of the Evil King spent 1:08 inside the room, an all-time record for the longest amount time spent on completing one room's objective.

Seasons Used 2
Layouts Used XI-XIII
Episodes Seen 44-71
Objective Completion 10
Temple Guard Encounters 9
Artifacts Featured The Heart-Shaped Pillow of Annie Taylor
The Ivory Elephant of Scheherazade
The Leopard Skin Cloak of Annie Oakley
Predecessor The Heart Room
Successor The Room of the Mandarin Hand
Adjoining Rooms The Observatory
The King's Storeroom
The Throne Room (Layout XI)
The Laser Light Room (Layouts XII and XIII)