The Labyrinth

In your dreams you wander a great labyrinth of an elder civilization. Every night you scour it for secrets, driven to understand the eldritch truth of this wasted civilization. The arcane knowledge you uncover bolsters your strength in the waking world, but digging too deep may reveal things better left undisturbed. Frenzied by the maddening knowledge layered within the dungeon, you are drawn further and further to the secret truths within. Is it real? Are you losing your mind? Does that even matter? The artifacts you unearth follow you to the waking world. Your power grows the further you delve. What lies at the center, and what will happen to you when you find it? 

As you journey deeper you may find knowledge or curios to aid you in the waking world. Beware that as your power grows, instability may too. The conflict of a dual existence takes a toll on the sanity of even the most steadfast prospector. Be careful of what you find, you may wish you had left well enough alone. 

Expanded Spell List

1st-level Labyrinth feature

The Labyrinth lets you choose from an expanded list of spells when you learn a warlock spell. The following spells are added to the warlock spell list for you.

Fathomless Expanded Spells

Spell Level	Spells
1st	dissonant whispers, sleep
2nd	arcanist's magic aura, tasha's mind whip
3rd	blink, hypnotic pattern
4th	black tentacles, summon aberration (star spawn only)
5th	legend lore, passwall

Augur of a Great One

1st-level Labyrinth feature

Early in your journeys through the labyrinth, you found the hint of an aberrant secret that stoked your wretched inquisitiveness. You can now conjure the spectral fragment of a Great One that strikes at your foes. It takes a horrifying form such as a writhing tentacle, a multi-jointed limb, or a pulsing node of energy. As a bonus action, you summon the fragment and one  creature within 10 feet of you to must make a strength saving throw. On a failure the target takes 1d10 force damage, is pushed away from you 5 feet, and is knocked prone.

You can summon the remnant a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.

A Hunter's Dream

1st-level Labyrinth feature

A hunter is a hunter, even in a dream.

While your body sleeps, your mind hunts ever deeper into the Labyrinth, invigorated by the search for long lost enigmas buried within. When you wake, the fragments of your ineffable discoveries remain with you. You gain proficiency in the Arcana skill. In addition you cannot be put to sleep by magical means.

Jaunt to the Labyrinth

6th-level Labyrinth feature

For you the barriers between the material plane and the labyrinth are thinned, allowing you to slip between them for a moment. When you are hit by an attack, you can use your reaction to gain resistance to all damage. The resistance lasts until the start of your next turn. During that time, you appear ghostly and translucent.

Once you use this ability you cannot use it again until you have finished a short or long rest.

Relic of Unnatural Vigor

10th-level Labyrinth feature

 Your zealous exploration of the unending Labyrinth has led you to a great discovery. You found a potent relic tied to the perplexing origins of the labyrinth itself. It may be in a form such as a stone tablet carved with runes of power, a chalice filled with the everlasting blood of a Great One, or a misshapen crystal pulsing with untold energies  When you awoke from the dream the relic returned with you, now inextricably linked to your spirit. While the artifact is in your possession you flesh is strengthened by otherworldly power. As an action you can gave yourself a number of temporary hit points equal to 1d8 + your Charisma modifier (minimum of 1 temporary hit point). You can use this action a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.

In addition, whenever you finish a short or long rest, your exhaustion level, if any, is decreased by 1. 

If you lose possession of the relic, it fades back into the dream world after one hour and the next time you return from the labyrinth it will be in your hands.

Unveil the Truth

14th-level Labyrinth feature

In your feverish dreams you have found the center of the labyrinth, and the mind-crushing truth that lies there. None but you can gaze on the truth and begin to comprehend what it means. Untold mysteries remain to be unearthed, but your mastery of the labyrinth has increased. You have learned how to magically drag the mind of another creature momentarily into the labyrinth, lifting the veil and forcing it to confront the incomprehensible reality. As an action, touch a creature within 5 feet of you. It must make an Intelligence saving throw against your warlock spell save DC. On a failed save, they take 4d10 psychic damage and are paralyzed until the end of their next turn as it try to rationalize the devastating revelation.

Once you use this feature, you can’t use it again until you finish a long rest.