Here are two duergars, based around the idea that their job is to fill one role so they don't have invisibility or enlargement. They're kind of designed after the Duergar Slaver and Duergar Champion minis.
Duergar Slaver, Level 3 Soldier
Medium Natural Humanoid (Duergar)
Init +3;
Senses Darkvision, Perception +2
HP 47;
Bloodied 23
AC 17;
Fort 15
Ref 13
Will 15
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Speed 5
Branding Iron (Standard; at-will) * Weapon, Fire
+5 vs. AC; 1d6+3 damage AND ongoing 5 fire damage (save ends)
Manacles (Standard; at-will) * Weapon
Reach 2; +6 vs. AC; 1d6+2 damage and the target is marked until the end of this creature's next turn. See also Entangling Manacles
Entangling Manacles (Swift; Recharge

)
When the slaver hits with Manacles; +6 vs. Ref; Prone
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Alignment Unaligned;
Languages Dwarven
Skills Intimidate +9
Str 16 (+4)
Dex 14 (+3)
Wis 12 (+2)
Con 15 (+3)
Int 12 (+2)
Cha 16 (+4)
Duergar Hammerer, Level 3 Brute
Medium Natural Humanoid (Duergar)
Init +2;
Senses Darkvision, Perception +1
HP 56;
Bloodied 28
AC 15;
Fort 17
Ref 12
Will 14
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Speed 5
Hammer (Standard; at-will) * Weapon
+6 vs. AC; 1d8+4 damage
Overhead Blow (Standard; at-will) * Weapon
+4 vs. AC; 1d8+8 damage.
Miss: Followup
Followup: +7 vs. Ref; Prone
Resounding Blow (Standard; encounter) * Weapon
+5 vs. Fort; 1d8+4 damage AND Dazed until the end of this creature's next turn.
Hit Them When They're Down
+5 damage against prone creatures
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Alignment Unaligned;
Languages Dwarven
Str 18 (+5)
Dex 13 (+2)
Wis 10 (+1)
Con 16 (+4)
Int 9 (+0)
Cha 12 (+2)