The Grand Archives are the last big area you have to clear before the end of the game. Good job making it this far! It's another dense area, with lots of levels stacked on top of one another, but it's also got a lot of useful upgrade items and weapons if you explore enough to find them. Now, this guide will help you with the exploring, giving you the quickest routes around the archives, but it's not going to spell it all out for you.
There is only one bonfire before the boss fight, and it's almost directly after the Dragonslayer Armour one. You basically just have to walk forwards for a bit. Given that there's only one bonfire here you might expect that the Grand Archives are a small, relatively simple area. This is, of course, not the case.
Appears after you defeat the Twin Princes, Lorian and Lothric, probably one of the creepiest boss fights in the game.
This sounds weird but we promise it makes sense in context. The area specific enemies for the Archives are all voluntarily covered in wax, like candles (we question the wisdom of doing this in a giant library, but who are we to judge?). At several points you'll come accross big basins full of wax and if you approach them you get an action prompt to stick your head in. You should definitely do this, a) because you look like a BDSM hot wax enthusiast after a serious weekender and it's hilarious, and b) because at many points in the Archives spectral hands will pop up out of the floor and shelves. They'll damage and stack curse on to you – unless you're in your giant novelty candle outfit.
You get in the Grand Archives by picking up a key in front of the main doors, which doesn't spawn unless you've already beaten three Lords of Cinder. You might remember, when you beat the Crystal Sage back on the Road of Sacrifices, that his soul said that the "twin Crystal Sages once served as spiritual guides to the scholars of the grand archives" so it shouldn't be that surprising that you run into the other one here. When you get into the archives he'll be in an alcove straight in front of him; start attacking him immediately. If you don't do enough damage to kill him immediately then he'll do the familiar disappearing act and reappear a couple of levels up in the Archives.
To get to his next location run left up some stairs, then turn right and drop down a ledge to run between rows of bookcases. Keep going straight until you see your first wax–headed scholar and carry on the direction he was going, which should see you turning left. In front of you now will be big stacks of books, more scholars, and a giant rectangular basin of wax. Go through the doorway to the right and up the right hand stairs in this dark room. Turn right again and go out into the main room of the Archives again, this time heading left. You should be able to see the Crystal Sage above you now, and he'll start casting spells again when you're in range. Instead of getting to him by going up the stairs and around, run forwards and on to the balcony in front of you. There's a ladder on the leftmost side that you can go up to come out on the balcony behind the Sage, avoiding the mobs on the stairs and most of the spells the Sage will throw at you. If you don't get him here he'll then teleport to the bridge over the middle of the Archives. To get there from the balcony you're on, run up the stairs to the left and keep going straight until you reach a broken bit of railing above the bridge. You can drop down here and finish the Sage off.
On the right, next to the Grand Archives bonfire, is a very, very long lift, which takes you up to the boss arena. But more on that in a moment. Most of the shortcuts you can open in the Archives involve kicking down ladders so you don't have to run around all the stairs every time you die. For the first one, start at the massive wax basin on the ground floor, go into the dark room on your right, up the stairs, and out. The kick ladder will be right in front of you, and goes down to the front of the ground floor, right of the alcove where the Crystal Sage first appeared.
From the top of this ladder run towards the balcony on the left and then keep going, curving right and around the whole circle of this walkway. That takes you to the bridge over the room. Run across it and into an empty stone room. Go around to the right and you'll find a lift, which takes you down to a room with a secret moving bookcase. Pull the lever to open it and voila! You're back on the ground floor again.
Right, hop back in that lift and take the right exit out of the room at the top, taking some stairs up and around to a kind of half circle mezzanine level, with a lot of bookshelves and waxy scholars about. Go across this to the doorway on the other side, through it, up the stairs, and out onto the roofs of the archives. Go left along the paved area you're on, down a ladder, and then onto the tiled roofs themselves. Keep going forwards and on to another long, paved walkway (not the square terrace on the right, which is lovely, but will take you nowhere, the walkway goes off straight in front of you). At the end of this is a steep, pitched roof leading up on your left, at the top of which is a gargoyle with a spear. From him you have two choices. Either go right until you see another balcony on the side of the archives, which you can walk into, or go left, doubling back on yourself but on a higher level.
For the latter you'll go around over a small dark tiled roof, always curving to the right, and eventually face off against two more gargoyles. Go on to the red tiled roof that they were patrolling on and drop down to the right, towards the big stained glass windows. You can get through a broken one here, and the next kick ladder is around the side of this walkway, back down to that mezzanine level with all the wax guys, so you can avoid all the roof malarky next time. If you chose the other route you'll come out on the same walkway, but at the opposite end of the room, so you have to walk slightly further to get to the ladder.
Alright, let's assume you've opened up that third shortcut ladder, and you've just gone up it. Run along the walkway until you reach a set of open doors on your left. Go through here, across the courtyard, and up the stairs (via three NPCs) into a candlelit room. There's a lift on your right which goes all the way down to the Grand Archives bonfire. This is your shortcut to the boss fight.
The Crystal Scroll is a guaranteed drop by the Crystal Sage in the archives. Give it to Orbeck of Vinheim back at Firelink Shrine to add some more sorceries to his shop.
Take the shortcut lift inside the archives (not the one up to the boss) and exit to the right, around to the mezzanine platform. Go up the ladder you kicked down earlier and the shard is on the corpse sat up in a chair in front of the stained glass windows. You may have already picked it up on your way through earlier.
Take the lift from the bonfire all the way up to the top. Exit the red-carpeted, candled room to the right, going up the stairs and out. Instead of heading forwards, towards the final boss fight, turn to your left and you'll find a staircase curving up around the domed roof behind you. Go up there and across the roof towards the rounded tower there. Proceed with caution: there are three angels on top of it, but you can avoid drawing aggro from them by skirting around the edge of the building using the narrow staircases.
There's a staircase leading into the tower at the centre of the roof. Directly opposite that staircase is another thin, narrow one that leads onto a wide rectangular roof. At the end of that is the shard. Nice work.
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