On this page you will find a description of the temple ruins in Cozumel in Shadow of the Tomb Raider (which are connected to the Hunter's Moon mission). This is the first larger location in the game and exploring it requires you to solve a few puzzles. Fortunately, they are not too difficult.
The flooded part of the temple
Squeeze through the passage to reach the first small ruin hall. Here you can see the monolith (and the mural that is one of the secrets). In order to go further you have to use the rope arrow on the multiple-rope knot shown in the picture at the barricade that blocks the passage. You don't have to choose the arrow type from your inventory. Just aim at the rope knot and Lara will automatically release the right arrow. Once the barricade is shot and pulled, it will be destroyed.
Immediately after unlocking the passage, take a few steps forward and stop at the line shown in the picture. This is a trap and if you touch the rope, the spikes will come out of the walls and kill Lara. Fortunately, you can activate the trap earlier by cutting the rope with a knife. After you disarm the trap, move under the spikes.
You will reach the cavern with a water reservoir. Jump into the water and dive as an underwater corridor leads to the next part of the ruins. While underwater, press and hold the fast swimming button as often as possible. Squeeze through the rocks. Along the way, make sure you use an air bubble to catch your breath. Always look after the air bubbles when you have to stay underwater for longer, which will reduce the likelihood of drowning. At the end of the passage, Lara has to squeeze back and forth between the rocks. Don't hesitate to make it as fast as possible to get to the surface.
Continue and cut the rope again to disarm the next trap with spikes. Climb up the wall and you will reach the huge cavern with a pyramid. Lara will have to reach the top of the pyramid.
The first puzzle in the ruins
Jump to further hanging structures with large bells. Finally, jump towards the vertical wall and bounce back into it to grasp the upper edge. Reach the location of the carriage. Aim at the multi-rope knot and pull out the barricade with a rope arrow. Push the wagon so that it starts to move. This will destroy a part of the structure.
Now, you can go further. Jump back on the bell constructions. Measure the last jump towards the partially broken ladder.
Stand by the pole with knot of ropes and aim at the next knot visible in the distance - it is shown in the picture above. Sending an arrow at this target will attach a rope between two shelves. You can catch the rope and move to the next location.
Go a bit further, jump on the new bell structure and make a jump towards the climbing wall. Grab it with your pickaxe and climb onto a larger shelf that includes a puzzle.
Second puzzle in the ruins
Lara's task is to destroy the new large barricade. Start by finding the wagon and pushing it to the central octagonal field shown in the picture.
Now get to the top mechanism shown in the picture above. Once you have interacted with it, you can rotate the standing carriage. Make sure the wagon turns towards the barricade that the mounted ropes knot is visible.
Stay in the same place where you turned the mechanism. Aim at a rope knot attached to the carriage with your bow. A connection will be created. Use the pickaxe to pull the wagon to the top structure - this is shown in picture 1. After the wagon has been pulled as much as possible, get near the rope and cut it with a knife (picture 2). The wagon will begin to descend and hit the barricade, unlocking further passage. This way, you will complete the puzzle.
You can now jump to the new bell structure and then to the new hanging ladder next to it. Climb up on a high rock shelf. Walk on it to the very end and jump to the edge. Turn right and use the climbing wall to reach the top of the pyramid. You can already descend on the rope.
A longer cut-scene will trigger. Also, you'll get the Chak Chel key. After watching the cutscene, head to the exit from the ruins. You'll also unlock the Dia de Muertos trophy. Reach the very end of the corridor and break through the weakened wall with your pickaxe - as shown in the picture. This will allow you to leave the ruins of the temple. Lara will reach previously inaccessible excavations.