The Elden Ring Gatekeeper Gostoc quest all happens within Stormveil Castle, so it's possible to complete it early on. It's a bit generous to even call it an Elden Ring quest (opens in new tab) as there are only a couple of steps, but it's easy to miss it completely as he can move around quite a bit within the castle.
Gatekeeper Gostoc is also a tricky sort and it turns out he steals 30 percent of your runes should you die inside the castle. It's possible to get these back, but you'll have to weigh up the consequences of doing so. Here's what you need to know about the Elden Ring Gatekeeper Gostoc quest and the main gate choice.
Elden Ring Gatekeeper Gostoc: Main gate choice
Elden Ring: Ranni's quest (opens in new tab)
Elden Ring: Blaidd's quest
Elden Ring: Millicent's quest
Elden Ring: Sellen's quest (opens in new tab)
Elden Ring: Fia's quest
Elden Ring: Irina's quest (opens in new tab)
Elden Ring: Varre's quest
Elden Ring: Hyetta's quest (opens in new tab)
Elden Ring: Thops' quest (opens in new tab)
When you first approach Stormveil Castle, you'll find the main gate is locked. You can enter the room to the left of the gate to find Gatekeeper Gostoc. When you talk to him, he'll suggest that instead of using the main gate, you should try another way.
If you accept his offer, you won't have to fight through the main gate which is heavily guarded, but you won't get access to his shop at this point. You can also find him at various points throughout the castle, though you'll have to hunt around for him. He's on the roof of the church where you meet Rogier for the first time. Then you can find him in the rampart tower, in the room with the lift, crouched over a corpse.
If you refuse his offer, he opens the gate and will become a merchant, but he won't show up in any other location and only move to Godrick's boss room once you've beaten the main Stormveil Castle boss. It's also important to note that you can refuse Gostoc's offer, have him open the gate, and take the side entrance anyway.
Whichever you choose, Gostoc will lock the door behind you when you enter the room containing the Rusty Key, which is required to progress further into the castle. Basically, this means you're trapped inside a dark room with a relatively tough Banished Knight enemy. If you die here, the door will remain unlocked so you can dash in and grab the key. Another —perhaps extreme—alternative is to kill Gostoc when you first meet him, so you don't get locked in the room in the first place.
If you want to retrieve the runes he steals from you whenever you die in Stormveil Castle, you should kill him before defeating Godrick the Grafted. He will drop Gostoc's Bell Bearing (opens in new tab), a Silver Pickled Fowl Foot, and a Glass Shard. His bell bearing means the contents of his shop will become available at the Twin Maidens Husks merchant at Roundtable Hold, but you'll miss out on a valuable item later on.
Stormveil Castle throne room
Once you've defeated Godrick, you can return to the boss room to find Gostoc stamping on what remains of the boss. If you decided to open the main gate for his merchant services, you'll find that his shop is no longer available.
He has one more role in both Nepheli (opens in new tab) and Kenneth Haight (opens in new tab)'s storylines, though if you decided to kill him, his absence won't affect either quest. Once the following requirements have been met, Gostoc, along with Nepheli and Kenneth, will move to the throne room in Stormveil Castle:
- Given the Stormhawk King to Nepheli.
- Spoken to Kenneth Haight at his fort in Limgrave.
- The boss, Morgott, has been defeated.
Once all three NPCs have moved to the throne room, Gostoc will reopen his shop and you can buy an Ancient Dragon Smithing Stone (opens in new tab) from him.
Elden Ring guide: Conquer the Lands Between
Elden Ring bosses: How to beat them
Elden Ring map fragments: Reveal the world
Elden Ring weapons: Arm yourself
Elden Ring armor: The best sets