From Software's games are infamous for many things. One of these is a very complicated side quest system. In Dark Souls 3 players have to complete several tasks and talk to the NPCs in specific places to progress their quests. And there are events throughout the game which can lock you out of certain side quests.
Dark Souls 3 continued this tradition. It has some very complicated questlines, even by FromSoftware standards. Some of these require very specific and non-intuitive steps and are likely to be overlooked by players on a blind playthrough. Others need you to perform some creative platforming to get to them or keep specific items that they need to progress their questlines.
Updated August 2, 2022 by Erik Petrovich: Questlines and sidequests DS3 offers players are convoluted, just as the flow of time is convoluted. In an organic playthrough, one might only complete one or two questlines using in-game clues and guidance. It's a bit of a shame, as most players completely miss out on the best quests in Dark Souls 3. Following a guide is easy enough for each of these DS3 NPC questlines, but be sure to follow them precisely or else risk ending it prematurely - or worse, killing the NPC unintentionally.
10 Siegward of Catarina
Getting to Siegward in a tower in the Undead Settlement requires some elevator acrobatics. After you meet him for the first time, he'll move to a wooden platform halfway up the tower. The elevators in this tower are not very straightforward either, with one going up and another going down from the same place.
Once you find your way up, you'll pass by his platform, and you might hear his signature hemming and hawing. His is one of the most iconic quests in DS3, truly one not to miss out on before fighting Yhorm the Giant specifically. If you do not find him in the Undead Settlement, however, you will completely miss his questline and condemn him to a lifetime of stasis in front of a fire demon.
9 Yoel and Yuria
Yoel or Yuria's sidequest requires a lot of non-intuitive actions. You won't really even find him if you're not one for searching every corner of the map obsessively. Or if you are put off by creepy moaning from what looks like a group of tastefully decorative corpses. But once you do talk to him, you have to go back and hollow yourself oh so many times before you reach a certain point or the quest will just end. If you succeed, however, you'll find Yuria and have to jump through more hoops (including a particular wedding ring) all for the chance to experience a different ending that you might mess up at the last moment by resting at a bonfire.
8 Irina
Unlike the first two, Irina is not a hard person to find. But you can easily mess up her entire questline and cause her to get corrupted and die. Irina is one of the NPCs who you can give magic tomes to, and she will let you buy spells from it. If you give her a couple of specific books, however, it will lock you out from the good ending.
Plus, if you do give her all the correct books but don't buy all the spells out, her quest won't be completed. It's a tricky one to complete depending on your decisions, but just be sure to follow the questline precisely as you play through Dark Souls 3.
7 Yellowfinger Heysel
The only way to initiate Heysel's sidequest is to having your ember restored at an area near the Road Of Sacrifices, and then fighting her. Later, you have to give a particular item to a particular person and summon her for the Abyss Watchers fight, and she ends up giving you a gesture.
But if you decide to pursue this quest, you will be locked out of a different NPC's sidequest, which the game doesn't exactly tell players. Unless you've been embered the whole time, it's easy to miss this NPC and the gesture reward.
6 Sirris of the Sunless Realms
Sirris is easy enough to find. She just shows up in Firelink Shrine after reaching the Road of Sacrifices and talking to Horace and Anri, at which point you can talk to her and begin her quest. However, keep in mind that if you do the steps to summon Yellowfinger Heysel for the Abyss Watchers fight, you'll lock yourself out of Sirris' quest.
Either way, Sirris makes players work to complete her questline, offering what is easily one of the most convoluted questlines in the game. Look up her questline from the beginning of the game, and be sure not to do anything that contradicts her - don't go collecting any pale tongues, so plan out future stat allocations ahead of time.
5 Orbeck
While Orbeck is not exactly hidden, he will refuse to talk to the Ashen One unless they have more than 10 intelligence. Once you do, you have to find a few scrolls and give them to him before the Abyss Watchers fight, or he will leave forever.
Also, if you have been continuing the Yuria sidequest, you'll get a mission to kill Orbeck, which will naturally bring a stop to his questline. It's really easy to lock yourself out of his story and all he has to offer if you are going for the Yuria quest, so try to complete his first.
4 Patches
The treacherous, treacherous Patches has been in every Soulsborne game in one form or another - even Elden Ring. He's something of a trickster, though he almost always turns friendly once confronted on his dastardly acts. Here, however, finding him is a lot harder than in the other games. To find the Patches NPC Dark Souls 3 players have to turn left just before the Deacons Of The Deep fog wall to open a shortcut, then leave the Cathedral completely and return through the shortcut.
After entering the Cathedral, you'll find a bridge with Siegward standing next to it. He tells the player of a treasure just across the bridge that he's leaving for them "right over there". After you start to cross the bridge, Patches takes off Siegward's armor and derides the player's greed as he pulls a lever to lower the bridge. Return back up, confront him on the other side, and his quest will properly begin.
3 Anri and Horace
Anri and Horace are not hard to find. However, their quest is very long, involves a series of esoteric steps, and has a diverging point. At this point, you have to choose if you want to follow her questline or get the Usurpation of Fire ending from the Yuria questline.
It's a brutal questline with many implications, and following it eventually forces players to decide whether to kill Anri or Horace. It's worth following for the sheer ridiculousness of a mute Gimp accompanying a noble knight, as well as the genuinely emotional moments experienced through the questline.
2 Archdragon Peak
Getting to Archdragon Peak is not necessarily a questline in Dark Souls 3, but it sure feels like one. The Nameless King and Archdragon Peak have become infamous for their difficulty, and for an area of such huge importance, it is really hard to get to. Fight Consumed King Oceiros first, which is not an easy fight, to get the Path of the Dragon gesture.
You may recognize the pose of this gesture from earlier, specifically from a group of stone dragons meditating near the Irithyll Dungeon. Make your way here, perform the emote, and you will be taken to Archdragon Peak after a short cutscene. Get past the Wyvern, a task easier said than done, to be able to challenge Gwyn's Firstborn, the Nameless King, and his giant dragon.
1 End Of Fire
Dark Souls III has four main endings, not counting the DLC ones. The End Of Fire ending has two versions, one of which is pretty straightforward. You get a pair of Firekeeper's Eyes from the Untended Graves and give them to the Firekeeper, and that's about it.
This will trigger a cutscene for the standard End Of Fire ending. But, during the final scene, you have a short window of time where you gain control of your character. If you kill the Firekeeper in this time, you get the alternate version of the End Of Fire ending - no spoilers, but it's definitely a bit different.
Dark Souls 3 is available now on PC, PlayStation 4, and Xbox One.