Finding Millicent’s prosthetic arm in Elden Ring takes you to a dangerous swamp castle full of poison (because this is a FromSoft game after all) as part of a much broader quest. Saving Millicent and following her quest to its conclusion influences one of the many Elden Ring endings, as well, but the journey to that point pits you against several challenging optional bosses.
Church of the Plague NPC
The woman dying from Scarlet Rot in Caelid’s Church of the Plague is Millicent. There’s nothing you can do for her until you speak to Gowry, who lives in a shack at the base of the cliff near the church. A relatively easy way to reach Gowry’s shack is heading south from the Church of the Plague, using Torrent to climb down the rot, and then following the road north under the fortress. Don’t stop for long if you take this path. The harpies lining the road will kill you quickly, and there’s an enemy who launches pots at you from the cliff.
Sneak around the zombie dog if you can, or just defeat it. Otherwise there’s a chance it will kill Gowry while trying to attack you (as shown in my heartbreaking but hilarious videos online). After speaking with Gowry, head west into Aeonia Swamp. There you’ll eventually find Commander O’Neill. Deal with the spirit summons the boss calls up first and avoid the Scarlet Rot cloud he spews. If you have poison weapons or magic, use that to exploit O’Neill’s weakness to poison.
Note that you can ride Torrent through this entire fight, too. A safe way to approach him is riding up, smacking once, and backing off. Just be patient.
Take the Unalloyed Golden Needle (a key item dropped by O’Neill) to Millicent at the Church, rest at the Site of Grace, then speak with her again until there is no new dialogue. Rest at the Site of Grace again. Then you can find Millicent at Gowry’s shack. Speak with her until there is no new dialogue. Again… You can also return later to talk to Gowry for additional context, if you like.
Where to Find Millicent’s Prosthetic Arm
The next time you’ll find Millicent is at the Erdtree Gazing Hill in Altus Plateau. Turn left after exiting the Dectus Lift, and you’ll run across the Site of Grace there, but there’s not much you can do for her right now. Travel northeast along the valley, west of the Second Church of Marika, and the valley eventually opens out onto The Shaded Castle. Otherwise push northeast from the Abandoned Coffin grace — if you came by way of the Ruin-Strewn Precipice. You can even summon Millicent for the Magma Wyrm boss fight that blocks your way up this path if you follow the steps with the needle.
Inside the castle, follow the walls around to the right and climb up the ruins to enter. Turn right again, walk along the ramparts, then turn left and go up the stairs to activate the Shaded Castle Ramparts Site of Grace. This is your starting point going forward. The Shaded Castle is full of poison foes and worse. Plus a strong enemy guards the prosthetic arm.
Drop down to the swamp from the Site of Grace, then turn west, and follow the poison until you see a tiled roof sticking out of the muck (just past a congregation of slugs). North of the sunken roof is a piece of dry land with a ladder — marked by a torch. Climb the ladder, veer left, and run along the ramparts (feel free to ignore or defeat the zombie enemies along the way). It leads to a small square with a red-caped Cleanrot Knight. If you’re not up for a fight, just run behind it and grab the Valkyrie’s Prosthesis from the chest. Then flee.
Take it back to Millicent at the Erdtree Gazing Hill Speak with her until no new dialogue shows up then rest at a Site of Grace.
Finishing Millicent’s Quest
If you want to finish Millicent’s quest, it will take some time and much more traveling. Her next location is Windmill Village (all the way to the northernmost part of Altus Plateau). Defeat the boss near Windmill Heights, then speak with Millicent until there is no new dialogue (again).
After that, she moves to the Ancient Snow Valley Ruins in the Mountaintop of the Giants area. You need to speak with her again here. The last location is the Brace of the Haligtree, the Prayer Room Site of Grace in Elpael. After uniting the Haligtree Medallion and defeating the Defiled Root Monster, you need to enter Millicent’s world (use the gold summon sign) and defend her. Similar to if you were playing multiplayer.
All of this, of course, requires you to get the Haligtree Medallion at all. The first half is in the Village of the Albinaurics in the far southwestern part of Liurnia (up a torchlit slope in another poison swamp there). You need to press through the area, beat the Perfumer mini-boss on the small plateau before the stone bridge, and finally punch a conspicuous pot next to a stone coffin on the slope below the boss. The pot is easy to find since it’s glowing. An NPC will appear to give you half of the medallion and a hint where to find the next.
“The next” isn’t available for a long, long time. It’s in Castle Sol — also in the Mountaintop of Giants region near the end of Elden Ring. You need to complete this dungeon and defeat its boss. Past him is a glowing item: the second half of the medallion. You can use the new medallion at the same place as the Grand Lift of Rold, in the Forbidden Land, after getting out of Leyndell. You need to select “hoist secret medallion” by switching from the normal “hoist medallion” option. Switch to it the same way you would switch between messages or item interactions (left or right on the D-pad by default).
Once inside this new zone — the Consecrated Snowfield — head dead north. There’s a small city populated with nonhostile spirits called Ordina, Liturgical Town. The only story relevant object here is a blue circle on the ground. Just like the ones found in Evergaols. That’s because it is an Evergaol. The objective is to light four torches throughout the town. However, you’re also being hunted by invisible Black Knife Assassins that can easily one-hit-kill players from behind.
The best way to fight this foe is with a Sentry’s Torch. You purchase this item from the vendor at Hermit Merchant’s Shack. That’s back in Leyndell: in the northwestern section of the battlefield area outside the capital. With this equipped, you can see the assassin coming and actually fight back. Once the puzzle is complete, you’ll reach yet another new area called the Brace of the Haligtree. Keep pushing through to the Drainage Channel Site of Grace. There’s a mini-boss to fight called the Defiled Root Monster in a rot lake just before the fight — just after you platform over some branches. Beat it, rest at the nearby grace, and you’ll finally find a summoning sign on the ground near where the mini-boss used to be. This will take you to an NPC invader fight alongside Millicent. Defend her.
Phew!
After all is said and done, Millicent will give you the Rotten Winged Sword Insignia and leave after you speak with her. Reset the area and return to where she summoned you to do so. Following that, retrieve the Unalloyed Gold Needle, defeat Malenia, and return the Gold Needle. You’ll get Miquella’s Needle instead: a key item used in Faram Azula. The item description suggests it alters the Frenzied Flame ending. Though at this point, we’re still unsure how it may do so specifically, if it does at all.
