Endless Horror

 is a quest in Torment: Tides of Numenera.

Synopsis
The Children of the Endless Gate have made a slaughterhouse of the Valley. The only way they'll leave is if I can close their Gate in the Necropolis, somehow. If the Gate's in the Necropolis, then the first step will be to find a way into the Necropolis tombs. The cultists have opened the Endless Gate somewhere in the Necropolis. I need to find it and figure out a way to close it.

Walkthrough

 * Get into the Necropolis tombs to find the Endless Gate. To do so, enter the Necropolis Entrance and talk to Motley. Unless you attack, you can persuade him to give you access to the prisoners he has, starting The Caretaker's Riddle.
 * After you complete the quest and learn the access code, activate the console (Guni). Motley will approach with his cultists (if he's alive), the memorialists in tow. Once he praises you, you will be faced with the prospect of him killing the captives.
 * You can watch the scene unfold... Or intervene. You can either attack Motley, facing a difficult fight in a very confined space, or use (Intimidation, Deception) to make them leave the Necropolis. He will drop a Scrawled Note as he leaves, with the code 5143.
 * Make sure to complete Severed Child to have the Twisted Metal Merecaster with you.
 * Enter the Endless Gate Entrance (1254). Enter the Endless Gate and find Inifere to the northeast.
 * Inifere is mad, it seems. He will speak in riddles, however, when you brandish the merecaster, he will recognize it. You will still need to use (Persuasion) or  (Intimidation) to make him use it. Then...
 * This mere is particularly fractured and difficult to follow. You will awake under the water, drowning. You can try to swim anywhere, but the body will die - and you will progress to the second part of the mere, meeting Marcysa, the founder of the Cult - and if you manage to use (Anamnesis), you will realise that she is a woman far worse than Inifere ever was.
 * Continuing, Inifere will eventually spring out of bed and take head in an ambush set to take down the Changing God, your father. However, the Sorrow crashes the party. You can inform Inifere of what it is, study it at his expense, order an attack, or spring the traps (forcing him to do it too). Everything comes down to naught and as the Sorrow slaughters the cultists, you are dragged into a room by Marcysa.
 * Before doing any other action, you can demand Inifere to give you the remains of Choi to store in your mind. Then you decide what to do, between entering the Endless Gate... Or facing the Sorrow as you should, ending Inifere's suffering before it began. Or you can bring him into the Endless Gate regardless.
 * Alternatively, you can use an alternative solution: Kill Inifere in combat, which is quite difficult, or convince him to leave the Valley, if he trusts you (interpret the dream correctly or make the correct actions in the mere, ones where you don't force your will on him). You can also convince him to kill himself to atone.

Back in "Reality"

 * Returning to reality brings resolution. If you decided to make Inifere die at the hands of the Sorrow, you will emerge at the Endless Gate Entrance, with a pile of goodies to pilfer and Quijano safely by your side.
 * If you did not alienate Ronos Cai'sul, return to him to receive the Brace of Mighty Kalas'Tor.