The biggest feature of the Mountain Pass in Baldur's Gate 3is the Rosymorn Monastery, which the githyanki have claimed and converted into Crèche Y'llek. The crèches are places for githyanki to raise their children safe from enemies, since time doesn't pass in the Astral Plane they call home.
Crèche Y'llek has several important Baldur's Gate 3 quests attached to it, and not all of them have to do with Lae'zel. Players can encounter a woman on the road to the monastery, and she'll ask the party to steal an egg from the crèche for the Society of Brilliance. Finding this egg isn't too difficult, but getting it out without a fight is much harder.
Updated September 5th, 2023: As players progress through Baldur's Gate 3, they'll come across an NPC named Lady Esther. This mysterious woman wants players to bring her a Githyanki Egg from a nearby creche. As players enter the nearby location, they'll likely come across a strange room filled with an acidic substance. Finding the Githyanki Egg in Baldur's Gate 3 is pretty simple if players know where to look and passing the appropriate checks can help them snag the prize without any bloodshed. To better help players in locating the Githyanki Egg in BG3, the following guide now includes a video.
Where to Find Lady Esther
The quest giver for the githyanki egg is Lady Esther. Her campsite is just to the northeast of the Trielta Crags waypoint. Specifically, players should descend the staircase to the north and then go around to the right.
Lady Esther doesn't make a good first impression. She's here to bring a githyanki egg to the Society of Brilliance, a group that hopes to raise the gith in a less abusive environment. However, Esther herself seems to think the exercise is pointless and a githyanki is doomed to be a hostile warmonger from birth. Still, the Society paid her well for her efforts, and she'll pay the party if they manage to do what she couldn't and retrieve an egg.
Crèche Y'llek Hatchery Location
Players have a few obstacles as they try to get from Lady Esther to Crèche Y'llek. There are the cliffs covered in repulsion mines (which players can bypass with a difficult Athletics check to activate the cable car). Then, there are the outer Rosymorn Monastery ruins, which are full of strange beasts and scavengers.
Eventually, however, players can find a large set of doors that lead to a lower level of the monastery. This level is where the githyanki have set up their crèche, and they obviously react with hostility when outsiders appear at the gate. Players can avoid combat by explaining themselves to the guards and passing a difficult social roll. Alternatively, they can let Lae'zel take the lead and get in without any trouble. From the entrance, take a left, then take a right, and then enter the large room full of acid pools.
How to Get the Githyanki Egg Peacefully
The hatchery is unusually empty, a fact Lae'zel will point out if she's present. It's also at the northwestern end of the chamber, and the way to it is full of hidden traps and pools of caustic acid. To avoid all of that, jump across the rocks straight ahead and then climb up to the githyanki standing on the overlook point just east of the egg.
This gith is Varsh Ko'kuu, the man in charge of the hatchery. He'll explain that the egg is the last of its group to hatch, and normally he would have to destroy the egg for taking too long. However, he's delaying his order for as long as possible, to give the egg every chance to hatch.
If the party member speaking to Ko'kuu passes an Insight check, they'll get to ask him for more information, and then get to choose a Persuasion, Deception, or Intimidation check to take the egg from him. If he agrees, he'll give the party Varsh Ko'kuu's Boots, which make the wearer immune to acidic surfaces (like the pool below) and take half damage from Acid sources.
Have a party member wear the boots, ungroup them, and then have that party member take the nearby ladder over to the egg. With Ko'kuu's permission, no one in the crèche will attack the party for taking the egg, and even Lae'zel won't change her opinion of the protagonist. Players can use the Trielta Crags waypoint to return to Lady Esther. Once she has it, she'll give the party a decent pile of gold and a promise that she'll show up again in Baldur's Gate.
Another option is to fight through the crèche and grab the egg along the way. If players choose this route, be sure to get Ko'kuu's Boots off his body before entering the acid.
Baldur's Gate 3 is available now on macOS and PC.