After you visit the Attlerock in Outer Wilds, you’ll have a rumor about Riebeck and Brittle Hollow’s Southern Observatory to investigate.
There are several paths to find Riebeck on Brittle Hollow, and they all have clues, information, and rumors to find along the way. There’s also the black hole at the center of the planet that you’re almost definitely going to fall into.
We’ll explore each of the paths to Riebeck below, and explain what to do when you fall into the black hole. Since the sun will likely go nova at some point while you’re exploring, you’ll have plenty of chances to start your journey at all three locations.
They all start at the Southern Observatory.
Land at the south pole of Brittle Hollow and look for the well-lit cave near Riebeck’s ship.
Inside, you’ll find a note from Riebeck saying he can’t get inside from here, and that he’s headed to some ruins to the north.
There are three places that look like ruins along the equator: the Gravity Crystal Workshop, the Tower of Quantum Knowledge, and Escape Pod 1. (There are actually four, but the one looks like a tower doesn’t have access to the underground, so we’ll ignore it for now.) All three have things to read and learn and will lead you to Riebeck. Since there’s a good chance the sun will go nova at some point while you’re exploring, we’re going to list them all below.
Option 1: Riebeck’s abandoned camp // Gravity Crystal Workshop
The easiest way to find Riebeck is to get back in your ship. From orbit, look around the equator for a depression with a few Nomai ruined buildings inside. Look for the depression in the ground, a dark wisp of smoke, and the four small, ruined buildings.
Find Riebeck’s abandoned camp and his notes. He’ll point you to the building blocked by trees.
Jetpack up to the roof of that building, and drop through the hole. Follow the stairs down, and then use the gravity crystals to continue down the wall to the Crossroads.
Option 2: Tower of Quantum Knowledge
From orbit, the Tower of Quantum Knowledge along Brittle Hollow’s equator looks a lot like a landing pad.
Set down nearby (or on top), and read all the Nomai script you can find. You’ll add information about the Quantum Moon and the nearby chunk of rock to your ship’s log.
Jump and jetpack to the top of that shard of black stone (it’s like the chunk in the Observatory on Timber Hearth, so it moves when you’re not looking at it) to read some more script and add it to your log, along with the locations of three other shards — we’ll get to them later.
Pull out your signal locator and point it at the shard to identify it as the Tower shard and add quantum fluctuations to your locator’s settings.
Head down the stairs attached to the tower. At the bottom of the stairs, there are signposts for nearby areas that we’re not worried about yet. Look for the elevator beam, and take it down.
The base of the tower is broken, so you can’t head up inside yet. Read any script you see, and then look for the sign pointing to the Crossroads. Switch the transportation beam on by moving the ball up, and step inside. The beam branches but rejoins in a bit, so just pick one and keep following along.
At the end, you’ll land at the Crossroads, and Riebeck will be on your left.
Option 3: Escape Pod 1 and Old Settlement
From your ship in orbit, use you signal locator to look along Brittle Hollow’s equator. You’re looking for an out of place spaceship-shaped thing and an unidentified signal. (It’s hard to describe, but pretty obvious when you see it.) Nearby Nomai text will identify this as Escape Pod 1 (of three).
Hop over to the escape pod and head inside. Read the Nomai script to learn that the Nomai arrived in the solar system on board the Vessel, and that there are two other escape pods.
Drop further down to find the escape pod hatch. Move the sphere to blow the door, and look down. You’re right above the Old Settlement, but the walkways are fragile and will give way as you walk on them. You’re very likely going to fall into the black hole and get transported to the White Hole Station (below).
To get to the Old Settlement, you’ll have to be quick and careful (and use your jetpack a lot). From Escape Pod 1, jump and jetpack across the collapsing wooden stairs to the stone ledge, and read the Nomai warning about the black hole beneath you.
Turn left and jump across the gap to the ramps. Follow them down and to the left. Once you’re on solid ground again, follow the stone path around until you find another Nomai note saying that the walkways here are stable.
Cross the first walkway, and take a right. Translate the script in the ruin to learn that the Nomai were here looking for a signal from the Eye of the Universe, and that the signal was older than the universe itself.
Turn right from that script and climb out of the building. Follow the path around to the left and across a bridge. Checking the other buildings for notes as you work your way down (there’s nothing for your log here — they’re just flavor text). Your goal is the lowest point in the Old Settlement.
When you get there, you’ll see a triptych — a three-part mural — on one wall and a Nomai note on the other. Look at the mural and read the note to learn that the Nomai came here in the Vessel following the signal from the Eye of the Universe, but the Vessel crashed into Dark Bramble. Two escape pods got out, but the third is still stuck on Dark Bramble. You’ll also learn that the Nomai wanted to build a more permanent and stable settlement — Hanging City.
Head back up to where you entered the Old Settlement. Take the path on your right when you’re returning to find a new note. This note will point you toward a gravity crystal path to the Hanging City. Follow the gravity crystals all the way across and through the ice caves. You’ll end up in the Hanging City — School district.
Riebeck’s camp // Crossroads
The Crossroads are a, well, crossroads under the surface of Brittle Hollow. There’s a mural on a nearby wall that explains where you are and where everything else of note is. The Hanging City is to the north, the Gravity Cannon is to the east, the Southern Observatory is predictably south, and the Tower of Quantum Knowledge is to the west.
Use the gravity crystals along the wall near the mural to descend one more floor. Follow your signal locator to go talk to Riebeck (and recharge your oxygen and jetpack).
Fittingly for a Crossroads, you’ve got several options for where to go next. Riebeck is pointing you toward Hanging City, so we’re going to head there. But we’re going to take the (very) long way around … by jumping into a black hole.