Duergar Darkmind (5e Creature)
From D&D Wiki
Medium humanoid (dwarf), lawful evil
Innate Spellcasting (Psionics). The duergar's innate spellcasting ability is Wisdom (spell save DC 13). It can innately cast the following spells, requiring no components:
Enlarge (Recharges after a Short or Long Rest). For 1 minute, the duergar magically increases in size, along with anything it is wearing or carrying. While enlarged, the duergar is Large, doubles its damage dice on Strength-based weapon attacks (included in the attacks), and makes Strength checks and Strength saving throws with advantage. If the duergar lacks the room to become Large, it attains the maximum size possible in the space available.
Flail. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 6 (1d8 + 2) bludgeoning damage, or 11 (2d8 + 2) bludgeoning damage while enlarged.
Handaxe. Melee or Ranged Weapon Attack: +4 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 5 (1d6 + 2) slashing damage, or 9 (2d6 + 2) slashing damage while enlarged.
Invisibility (Recharges after a Short or Long Rest). The duergar magically turns invisible until it attacks, casts a spell, or uses its Enlarge, or until its concentration is broken, up to 1 hour (as if concentrating on a spell). Any equipment the duergar wears or carries is invisible with it.
Some duergar are trained in the psionic arts, with the ability to drain the light from an area or move objects through force of will alone. In duergar society, darkminds serve as investigators and interrogators, mentally searching their victims' minds for answers.