Duergar (pronounced: /ˈdjuːɜːrgɑːr/ DEW-ur-gar), also known as gray dwarves, were a subterranean race. They carved out an existence in the Underdark, often near volcanoes. Their kinship to other dwarven subraces could be compared to that of the drow to surface elves.
Like their other dwarves, duergar were typically stocky figures, though beyond this there were many differences. Both male and female duergar were typically bald, with females also lacking the capacity to grow facial hair. Many were also thinner than their dwarven brethren. Most obvious, however, was their dull gray skin and hair, often matched with an equally stolid expression. Duergar were brought into the underdark in persuit of wealth fortune and new lands, as well as some persuasion from mindflayers. Many large groups of Duergar are still under control of mindflayers as slaves, but there is still a few kingdoms who are not. to to say they are the most sane individuals
Because many duergar found on the surface world were criminal exiles, a surface dweller who encountered one of the gray dwarves was likely to notice facial and arm tattoos that marked the duergar as a traitor to his or her people
Ability Score Increase.
Your Strength score increases by 1 and Your Constitution score increases by 2.
Duergar stand between 4 and 5 feet tall and average about 150 pounds. Your size is Medium.
You have advantage on saving throws against poison, and you have resistance against poison damage.
Dwarven Combat Training:
You have proficiency with the battleaxe, handaxe, throwing hammer, and warhammer.
Tool Proficiency: You gain proficiency with the artisan's tools of your choice: smith's tools, brewer's supplies, or mason's tools.
Whenever you make an Intelligence (History) check related to the origin of stonework, you are considered proficient in the History skill and add double your proficiency bonus to the check, instead of your normal proficiency bonus.
You can speak, read, and write Common and Dwarvish. Dwarvish is full of hard consonants and guttural sounds, and those characteristics spill over into whatever other language a dwarf might speak.
Your base walking speed is 25 feet. Your speed is not reduced by wearing heavy armor.
Your darkvision has a radius of 120 feet.
You can speak, read, and write Undercommon.
You have advantage on saving throws against illusions and against being charmed or paralyzed.
When you reach 3rd level, you can cast the enlarge/reduce spell on yourself once with this trait, using only the spell's enlarge option. When you reach 5th level, you can cast the invisibility spell on yourself once with this trait. You don't need material components for either spell, and you can't cast them while you're in direct sunlight, although sunlight has no effect on them once cast. You regain the ability to cast these spells with this trait when you finish a long rest. Intelligence is your spellcasting ability for these spells.
You have disadvantage on attack rolls and on Wisdom (Perception) checks that rely on sight when you, the target of your attack, or whatever you are trying to perceive is in direct sunlight