This is yet another tutorial story quest. This time, you’ll learn the basic survival skills. After that scene, pick up the salvebrush and press the up button to consume it. Your pouch can only hold a finite amount of herbs which is represented by the thin green bar under your HP.
Continue following Rost and he’ll then instruct you to hide in the tall grass ahead. Take note that in the entire game, this red-tipped grass is the only type of vegetation in the game where you can hide from machines and hostile humans. After the first watcher passes by, follow Rost to the next patch of grass. Let the second watcher pass then follow Rost to the next patch of grass. Like the others, let this third watcher pass as well.
Continue following Rost along the trail until a cutscene triggers. After the scene, continue following Rost as he crosses the stream and chases off the herd of striders. He then tells you to gather rocks. There will be several rocks nearby so pick up three of them then follow Rost until you locate the machines.
Rost will go down and hide in the tall grass below so you’ll have to thrown the rock near him to get the watcher’s attention and lure it to Rost. He will then finish off the machine with a Silent Strike . Regroup with Rost and loot the watcher’s remains.
He’ll then instruct you to gather some ridge-wood from the nearby plants. After gathering enough wood, he’ll teach you how to make arrows. The weapon wheel will also allow you to craft ammo from any currently equipped weapon, provided that you have the necessary materials to craft them.
After crafting your arrows, follow Rost as you sneak up to the nearby striders. After the short scene, use your Focus and examine the nearby strider’s components to learn its weak spots. Rost will then tell you to shoot the eye or the canister. Full-draw your bow and aim for the canister. This will deal a significant amount of damage to the strider but won’t kill it immediately. Shoot its eye or if you have no choice, its body to destroy it. Once done, loot the strider’s carcass.
Once done, follow Rost to check out the commotion. Upon reaching the site, a cutscene will play. After the scene, you’ll be controlling Aloy once more. This time, you have to use stealth to reach the boy and guide him to safety. You only have to look out for the watchers since they’re the ones roving around. As long as you don’t get too near the striders, they won’t notice you.
For the first watcher, highlight its track with your Focus then move to the next patch of grass ahead. Take note that you can use your rocks to distract them and force the watchers to investigate the source.
After reaching the next tallgrass patch, find the next nearby watcher and tag/highlight its tracks. Move to the next patch of grass beside the rock and dead tree trunk. Move only when the watcher patrolling this immediate spot has begun walking away. Upon reaching the grass by the stream, move towards the next patch of grass in the other side. Sneak by the last watcher and find Teb behind the concrete ruin.
After reaching Teb, follow the objective marker and time your movement to avoid the last watcher patrolling the path. After sneaking past the last watcher, a scene will trigger upon reaching safety. You’ll also unlock a story-related trophy (Followed Rost’s teachings).
The entire sequence will be shown in the video below:
During the scene on the way home, you’ll get a Flashpoint moment. This will give you three emotional choices and will show Aloy’s personality in key moments. Some of these choices carry permanent repercussions later in the game and should not be taken lightly, (not at least the later flashpoints) For this moment, it will only affect your conversation with Bast years later, when you meet again as adults.