They’ll tell you about a way to get Unuratu back, and Uchu will give you a uniform that you’ll put on. It’s useful because it basically allows you to get past the Trinity guards in most cases.
Head towards the location on the map and walk through the area until you reach Etzli. He’ll tell you where to go, but he’ll also tell you about someone who will give you a side quest, you can take it if you want.
Talk to the two guards, then head into the prison and follow the path.
You’ll eventually come to a cutscene where Unuratu and Amaru discuss the issues at hand. Amaru will tell Unuratu that someone already took the box 400 years ago: Andres Lopez, a missionary.
Go towards the path and you and Jonah will talk about saving Unuratu. There’s a Challenge Tomb here, so be sure to pick it up if you want to get the skill here.
Continue down the path, and you’ll eventually come to an area where you can go left for the Challenge Tomb or right to continue the story. There’s also a mural here, so be sure to pick it up.
Go down the right path, and you’ll eventually get to Unuratu’s cell. You’ll have a talk with her, and you’ll decide to go to the tomb of the last emperor of Paititi. Lara will ask Unuratu to take her there, and you guys will be on your way.
Knock down the wall in the cell and you and Unuratu will seperate briefly. Make a rope tether to the other side of the area and slide down it.
Keep going down the path, making sure to read the mural (and monolith, if you can read it) along the way, and a small cutscene will play out in which Unuratu kicks some Trinity ass and gets her own clothes like yours. Another cutscene will play in which Unuratu will tell you she’ll have to resist the desires that the box shows her in order to save the sun. If she messes up, then the “crimson fire” will hold her to her promise.
After she dies, a bunch of warriors will come for you. Defeat them, and head outside once you’ve done so.
This is actually a pretty easy fight, just stealth kill all of them one by one by using the central shrubbs when they walk in front of you. Wait until they’re not visible by others to do so, however, or else you’ll get aggro’d. If you do, though, you can just sit in the leaves again until they walk up and you can stealth kill them again. Using this tactic you can basically stealth kill every single one.
A cutscene will play out in which you’ll meet with Jonah, as well as Etzli and Uchu, and bear the bad news of Unuratu’s death. Then you and Jonah will be on your way to try and figure out what the clue meant.
She’ll wash up on a beach and fight a Trinity guy, but win against him after a grueling fight. Afterwards, there will be a few enemies right after. Go over to the right bush and stealth kill the guy there.
After they’re dead, head up the area and you’ll find a new base camp, The Beach. Rest at it and continue on, you’ll find that Commander Rourke has found out about you tuning into his radio frequency. Keep going down the path and you’ll reach some more soldiers, but this time they have thermal goggles. They’ll find you in brushes and the like, UNLESS YOU HAVE MUD ON YOU. If you get some mud on you, just stealth kill all the guys here to deal with them.
Once you’ve dealt with them, head down the path. You’ll eventually reach a cave which contains a bow that you can use. Keep going down the path and you’ll come to a tree you can climb. You’ll see a couple of enemies there and gain access to some fear arrows.
This will be an introduction to fear arrows, they will cause the person to not figure out where you are, and then shoot nearby enemies, and then die himself. They are very useful, and since they cause the person to die, it is recommended you use them on the armored enemies with helmets.
Once you’ve killed the guys in this immediate area, you can stealth kill the ones up ahead similarly using the branches and the cover. Essentially, you can clear a ton of these guys by shooting the armored ones with the fear arrows from a distance and stealthily taking out the rest.
Some of them have thermal goggles however, so be careful! There are mud patches in the area you can use to cover yourself.
After you’ve murdered them all, Commander Rourke will tune into your radio frequency and tell you that Jonah is dead.
Keep going down to the refinery, and you’ll have a large chase sequence the ends with you murdering a soldier. Then you’ll scare two of them, and have to fight them right after, alongside a bunch more trinity soldiers afterwards.
Once you get to the helicoptor part, just stay behind the cover and try and kill as many guys as you can. Eventually, the helicoptor will explode and you’ll have a cutscene where Lara wakes up to see Jonah alive. Lara will have a small tantrum and you guys will decide that you need to go to find a Church of San Juan, one that is within trekking distance of Paititi.
Once that’s done with, you and Jonah will decide to head to find the Church of San Juan!
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