Board Thread:Dark Souls III/@comment-27328111-20160418195320/@comment-28391607-20160519131151

First off, I refer to Anri as a "her" or "she" as my playthrough was with a male.
 * SPOILERS AND DIRECTION OF USURPATION OF FIRE ENDING************
 * SPOILERS AND DIRECTION OF USURPATION OF FIRE ENDING************
 * SPOILERS AND DIRECTION OF USURPATION OF FIRE ENDING************
 * SPOILERS AND DIRECTION OF USURPATION OF FIRE ENDING************
 * SPOILERS AND DIRECTION OF USURPATION OF FIRE ENDING************

Secondly, NEVER use the firekeeper to heal your hollowing. Some say a purging stone or the prayer statue in the undead settlement is okay to use to maintain the human appearance but I ask, "Why risk it unless YOU know for sure" so I avoid touching anything that brings my human appearance. Do the following:

1) Rank up 5 times with Yoel (two deaths allow each rank up) 2) Talk to Anri and Horace at Road of Sacrifices and be sure to ALWAYS EXHAUST DIALOGUE (they tell you they are essentially on same path as you) 3) Talk to Yuria of Londor (next to Yoel who should now be deceased). 4) Defeat Deacons of the Deep (Both Horace and Anri can be summoned here, be careful not to let them die in the fight by using alluring skulls.) 5) Talk to Yuria at Firelink Shrine along with Anri and Horace (standing near one of the thrones.) 6) Find Anri in Catacombs of Carthus (head up the ramp where the skelley-ball continually goes up and down. Once you reach the top continue to hug the right wall turn after turn until you find Anri standing in a corner). She will ask if you know Horace's whereabouts and you always say "NO" ***(if you have additional dialogue and you tell her you know she will go looking for him and die ending the questline.) 7) Continue forward to find Anri further in the catacombs (near the bridge leading to High Wolnir) and speak with her again (she should still be "Horace-less") Again, you know nothing about his whereabouts (****otherwise she finds him and ends the questline.) 8) Head down to Smouldering lake. The moment you enter the large swamp area where the Giant Avelyn shoots you, keep to the right. As long as you follow the right wall you will find the cave that has Horace in it. Kill him as he is hollowed. 9) Return to Anri and talk with her. YOU DO NOT KNOW WHERE HORACE IS when she asks (***otherwise questline ended) 10) Kill Wolnir and continue forward to Irithyll of the Boreal Valley. At the Central Valley Bonfire, be sure to head back to firelink and talk with Yuria (who should now be calling you their Lord and suggesting you take up Anri as your wife/husband.) 11) Fight through Irithyll until you get to the Yorshka Church where you will find Anri near the bonfire. Speak with her and now she displays a bit of courage and is ready to continue on her mission to find and kill Aldritch. There is a group of statues here, in the corner near the entrance. Among them are an assassin using chameleon. 12) Defeat Pontiff Sullyvhan (Anri can be summoned here but not necessary) 13) Return to Firelink Shrine and speak with Yurla who will tell you your wife/husband is ready for the ceremony. 14) Make way to Gwyndolin's (Dark Souls 1) old tomb (essentially run through area until you get to the spiraling elevator that leads upward to bonfire/boss, but instead of using elevator to go up, hit an illusory wall in the room before the spiraling elevator.) 15) talk to the pilgrim at the beginning of the corrider (he was the assassin) who gives you some "Vow" item that you take down the hallway and place into Anri's deceased body to activate the ceremony). Be sure to go back to the assassin pilgrim who should be deceased now (if not rest at bonfire and return) to get chameleon sorcery. 16) Talk to Yurla at firelink 17) Beat the game :)
 * (1a) killing the assassin ensures Anri lives and you can help her defeat Aldritch in her world only but this will end the Usurpation of Fire ending questline.
 * (1b) leaving the assassin to live will continue forward the Usurpation of Fire ending ultimately killing Anri.

Im about 95% sure this is completely right. Ive done the questline myself, but if for some reason I made a mistake I hope someone mentions something quick. The main theme here is to continually check up on Yurla for extra dialogue, but be sure to find Anri in all those places I mentioned.