Warlock Patron

Magic Resistance. The warlock patron has advantage on saving throws against spells and other magical effects.

Legendary Resistance (3/day). Whenever the warlock patron fails a saving throw it can choose to succeed instead.

Indomitable Will. In my groups home games we use a 7th ability score known as Will. If someone wishes to use this stat then the Warlock Patron's Will score is 30 (+10)

Spellcasting. The Warlock Patron is a 19th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 24, +16 to hit with spell attacks). The Warlock Patron has following Warlock spells prepared:
Cantrips (at will): Chill Touch (A), Eldritch Blast (A), Thunderclap (A)
1st level (4 slots): Shield (R), Chaos Bolt (A), Command (A)

2nd level (3 slots): Misty Step (BA), Shatter (A), Earthbind (conc) (A)

3rd level (3 slots): Counter Spell (R), Enemies Abound (conc) (A), Vampiric Touch (conc) (A)

4th level (3 slots): Banishment (A), Summon Aberration (conc) (A), Dimension Door (A)

5th level (3 slots): Dance Macabre (conc) (A), Synaptic Static (A), Hold Monster (conc) (A)

6th level (2 slots): Mental Prison (conc) (A), Scatter (A)

7th level (1 slot): Finger of Death (A)

8th level (1 slot): Maddening Darkness (conc) (A)

9th level (1 slot): Blade of Disaster (conc) (BA)

Multiattack. The warlock patron makes two Longsword attacks. Additionally, the warlock patron crits on a 19 or 20 on the die roll.

Sword of Unholy Pain. Melee Weapon Attack: +17 to hit, reach 10 ft., 1 target. Hit: 35 (4d12 + 9) slashing damage. If a creature is critically hit by this weapon they must succeed on a DC 24 Wisdom saving throw. On a failure the target takes an additional 22 (4d10) psychic damage or half as much on a success.

Frightful Presence. Each creature of the warlock patron's choice that is within 120 feet of the warlock patron and aware of it must succeed on a DC 24 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the warlock patron's Frightful Presence for the next 24 hours

Charming Demeanor. The Warlock Patron chooses a creature within 120 ft. of it that it is aware of and attempts to charm the creature. The target must succeed on a DC 24 Wisdom saving throw or be charmed by the warlock patron as if under the Dominate Person spell. The warlock patron can have up to three creatures charmed in this way. When a creature breaks the charm or the effect ends for it that creature is immune to the warlock patron's Charming Demeanor for 24 hrs.

Spell Slinging. The Warlock Patron can cast a single target spell as a reaction for an opportunity attack.