Last Emperor (The Hidden City)
Break the wall in Unuratu’s prison cell and exit. Use rope-tether to cross the river and grab the ledge, shimmy left, and climb up. Jump forward and throw grapple-axe to in mid-air to grab the crabby wall ahead. Shimmy left, climb up and takedown the guard standing near the ledge. Now, keep following Unuratu until you reach the Tomb of Sinchi Chiqa.
Enter and Explore the Tomb of Sinchi Chiqa
Go down the stairs towards left and climb the wall just in front of the stairs (look for the white patch on the wall). Then climb up to get to the top of statue’s right hand. Then jump over to the left hand using grapple-swing in mid-air. Jump and use grapple-axe to enter the open passage in the tomb. Atart exploring the tomb and a cut-scene will start after a while.
Defeat the Cultist Warriors
After Unuratu’s death, cultist warriors surround Lara in the Tomb of Sinchi Chiqa. There are around 12 warriors and you’ve to defeat them before exiting the tomb. The cultist warriors are quite tough. Its better you kill as many as you can while in stealth. Hide in the bushes and wall-plantations to maintain stealth. Chain takedown skill could be useful here. After taking out all the warriors head out through the main gate. Jonah will be waiting for you outside and a cut-scene will start.