Your patron is a mysterious entity whose nature is utterly foreign to the fabric of reality. It might come from the Far Realm, the space beyond reality, or it could be one of the elder gods known only in legends. Its motives are incomprehensible to mortals, and its knowledge so immense and ancient that even the greatest libraries pale in comparison to the vast secrets it holds. The Great Old One might be unaware of your existence or entirely indifferent to you, but the secrets you have learned allow you to draw your magic from it.

Entities of this type include Ghaunadar, called That Which Lurks; Tharizdun, the Chained God; Dendar, the Night Serpent; Zargon, the Returner; Great Cthulhu; and other unfathomable beings.

Expanded Spell List

The Great Old One let's 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.

Great Old One Expanded Spells

Spell Level	Spells
1st	dissonant whispers, tasha's hideous laughter
2nd	levitate, alter self
3rd	sending, summon undead
4th	arcane eye, evard's black tentacles
5th	bigby's hand (appears as a tentacle), legend lore

Induce Madness

 Starting at 1st level, the forbidden knowledge you acquired can cripple the minds of those that fail to understand it.

 As bonus action you can scramble the mind of a creature within 30 feet of you that can hear and see you, that creature is inficted with madness for 1 minute, a mad creature has disadvantage on attack rolls and saving throws and it must make a wisdom saving throw against your spell save DC at the start of it's turn becoming paralysed on a failed save until the start of it's next turn. The madnnes ends early if the target dies, you die, or you are incapacitated.

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

Even Death May Die

 Knowledge of the great old ones has revealed hidden civilizations build by thier offspring and their secrets to eternal life.

 Starting at 6th level, when you use a warlock spell slot you gain temporary hit points equal to the slot level + your bonus proficiency.

Create Thrall

 Starting at 10th level, you can befriend and sometimes even recruit people under your services using your silver tongue as well as a bit of magic.

 Once per short or long rest as an action you can touch a creature forcing it to succed on a charisma saving throw against your spell save DC or be charmed for 1 hour, a creature makes this save with advantage if you or your friends are fighting it, the effect ends early if you or one of your allies hurts it or if you ask something that would directly harm it, when the effect ends the creature knows it was charmed by you.

*Second Stage: A creature that was charmed suffers horrific nightmares for the next 3 days, it must make a wisdom saving throw with disadvantage during each day against your spell save DC, on a faillure it gains a form of permanent madness and if the creature fails all saves it becomes charmed by you until a Remove Curse spell is cast on it or the charmed condition is removed from it. A creature can't be indefinitily charmed if you already have an indefinitely charmed creature under your control.

Mass Madness

Starting at 14th level, you can influence large crowds of people with your patreon's magic.

 As an action every creature within a 30-foot cube centered on you that can hear and see you becomes inflicted with madness for 1 minute, a mad creature has disadvantage on attack rolls and saving throws and it must make a wisdom saving throw against your spell save DC at start of it's turn, becoming paralysed on a failed save until the start of it's next turn. The madness ends early if the target dies, you die, or you are incapacitated.

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