Cornelius Strongarm Revived

Duergar Resilience. Cornelius has advantage on saving throws against spells, and illusions, as well as to resist being charmed or paralyzed.

Sunlight Sensitivity. While in sunlight, Cornelius has disadvantage on attack rolls, as well as on Wisdom (Perception) checks that rely on sight.

Shroud of Fog. Cornelius can cast Fog Cloud twice per day.

Summons. Once per day, Cornelius can ritually summon an imp or quasit as if by the spell Find Familiar.

Touch of the Dead. If Cornelius reduces a creature to 0 hit points, he regains 20 hit points.

Fiend's Curse (2/Short Rest). Cornelius casts one of his spells as a bonus action without expending a spell slots.

Necromancer's Blessings. Creatures hit by Cornelius's Eldritch Blast or Ray of Enfeeblement must make a DC 18 Charisma saving throw. On a failure, they move 15 feet in a direction determined by Cornelius.

Spellcasting. Cornelius is a 5th-level spellcaster. His spellcasting ability is Intelligence (spell save DC 16, +8 to hit with spell attacks). Cornelius has the following Warlock spells prepared: 
Cantrips (at will): Chill Touch, Eldritch Blast, Mage Hand
3rd level (2 slots): Burning Hands, Command, Comprehend Languages, Hellish Rebuke, Blindness/Deafness, Hold Person, Ray of Enfeeblement, Scorching Ray, Counterspell, Fireball, Fly, Stinking Cloud

Pact of the Chain. Whenever Cornelius takes the Attack action, his familiar can make one attack at the same time.

Enlarge (Recharges after a Short or Long Rest). For 1 minute, Cornelius magically increases in size, along with anything it is wearing or carrying. While enlarged, Cornleius is Large, doubles his damage dice on Strength-based weapon attacks (included in the attacks), and makes Strength checks and Strength saving throws with advantage. If Cornelius lacks the room to become Large, he attains the maximum size possible in the space available.

Painful Warhammer. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: (2d8 + 4) bludgeoning damage. If enlarged, this weapon deals 3d8 + 4 damage.

Javelin. Ranged Weapon Attack: +9 to hit, reach 30/120 ft., one target. Hit: (2d6 + 4) piercing damage. If enlarged, this weapon deals 3d6 + 4 damage.

Invisibility (Recharges after a Short or Long Rest). Cornelius magically turns invisible until he attacks, casts a spell, or uses his Enlarge, or until his concentration is broken, up to 1 hour (as if concentrating on a spell). Any equipment Cornelius wears or carries is invisible with him.