Warlock Pact - The Threshold

There exist places that hunger for connection. Feeding off of emotion, presence, and the twisting and corruption of both. These locations aren't uncommon. Derelict mansions, forgotten halls, abandoned inns all longing for the lively spirits that once resided within. But some places are special; Some hunger so strongly to hold onto these spirits that they refuse to relinquish them even in death. Your patron is such a place. You are it’s grasping hand into the world beyond it's walls.

Steward of the Halls

At first level a warlock bound by their Threshold may manifest a mirror of their patron’s halls once per long rest. This feature functions identically to the spell “Magnificent Mansion” with a number of limitations that are absolved as the warlock levels up.

Warlock Level	Condition of the Hall
1st	The mirror of the patron’s halls appear dark dusty and dilapidated with a lack of any servants, food, or accommodations. Individuals other than the warlock sleeping within these halls must make a DC 15 wisdom saving throw. Failure indicates they were frightened over the course of the night by the spirits within the walls and were unable to gain a full night’s rest. They begin the day with 1 point of exhaustion. Furthermore the door created by this spell always glows with a faint ghostly blue fog and does not turn invisible. The door has an ac of 16 and hp equal to 3x the warlock's max hp.
4th	The hall presents itself lit by smokey lanterns and it’s condition is markedly improved. Upon arrival a simple but enjoyable meal can be found ready within fit for a number individuals equal to 3 plus the warlocks charisma modifier. The wisdom saving throw to sleep in the building is reduced to 10.
8th	The hall is now clean and presentable with warm hearths and a pantry of quality food. A team of spectral butlers and maids equal to 3 plus the warlock’s charisma modifier are present within the walls that are able to attend to the needs of the guests, albeit with some quiet hostility to those other than the warlock. Furthermore the door now turns invisible while closed as per the "Magnificent Mansion" spell.
11th	The mirror of the patron’s hall now functions identically to the spell “Magnificent Mansion” Guests are no longer required to make wisdom saves against exhaustion at night.
14th	The mirror of the halls and the physical hall itself become one. The halls now function as a “Demiplane” spell tied directly to the location of the patron’s walls. The warlock gains the following lair action* : The warlock may teleport any target (including themselves) within line of sight to any location within the building. If the target may make a will saving throw with a DC equal to the warlock's spell save DC.
17th	The warlock may now summon their patron building in its entirety to a location. There must be enough room to accommodate the building to use this ability. The warlock gains the following lair action* : The warlock casts phantasmal force (no components required) on any number of creatures it can see within the building. While maintaining concentration on this effect, the warlock can’t take other lair actions. If a target succeeds on the saving throw or if the effect ends for it, the target is immune to the warlock’s phantasmal force lair action for the next 24 hours, although such a creature can choose to be affected.
*	The warlock may only take a single lair action per round on initiative 20.

Servant's Passage

Starting at 6th level the warlock gains access to the servant's passage, an unearthly gate The Threshold provides to quickly move about it's grounds. As a bonus action you may create a pair of ephemeral wrought iron gates cloaked in dense fog which breaks vision traveling through either gate. These two gates may not be further than 30 feet from one another and both must be within line of sight at the time of using this ability. Any creature may enter one gate and emerge out of the other. The gate remains open for a number of rounds equal to the warlock's charisma bonus. The warlock must maintain concentration on this ability for it to remain open. The warlock regains the use of this ability after a short rest.

Among the Departed

Starting at 10th level you gain the ability to become that which resides within your patron's hall. As a bonus action, for a number of rounds equal to half your warlock level, you may become ghostly and gain the following abilities. The warlock may return to their corporeal as a bonus action during their turn. The warlock regains expended rounds after a short rest.

Forced Vacancy

Starting at 14th level you gain the ability to possess a target while in ghost form. You may expend a warlock spell slot to attempt to possess one humanoid target that you can see within 5 feet. The target must succeed on a charisma saving throw equal to your spell save DC (creatures warded by a protection from evil and good or magic circle spell can't be possessed). If the target fails the saving throw you possess their form. While in their body you do not expend rounds of "Among The Departed". Once you possess a creature's body, you control it although you don't deprive the target of awareness. You can't be targeted by any attack, spell, or other effect, except ones that turn undead, and you retain your alignment, Intelligence, Wisdom, Charisma, and immunity to being charmed and frightened. You otherwise use the possessed target's statistics but don't gain access to the target's knowledge, class features or proficiencies. The possession lasts until the body drops to 0 hit points, you end it as a bonus action or you are turned or forced out by an effect like the "Dispel evil and good" spell. When the possession ends, you reappear in an unoccupied space within 5 feet of the body in your corporeal form. The target is immune to your possession for 24 hours after succeeding on the saving throw or after the possession ends.