Sources
CR
Type
Size
Alignment
Movement

Duergar Hammerer

Medium Construct (dwarf), Any alignment

Armor Class 17 (natural armor)
Hit Points 33 (6d8 + 6)
Speed 20 ft.
STR
17
+3
DEX
7
-2
CON
12
+1
INT
5
-3
WIS
5
-3
CHA
5
-3
Damage Immunities poison
Condition Immunities Charmed, Exhaustion, Frightened, Paralyzed, Petrified, Poisoned
Senses darkvision 60 ft., passive Perception 7
Languages understands Dwarvish but can't speak
Challenge 2 (450 XP)

Traits

Siege Monster. The hammerer deals double damage to objects and structures.

Actions

Multiattack. The hammerer makes one Claw attack and one Hammer attack.

Claw. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit:6 (1d6 + 3) piercing damage.

Hammer. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit:10 (2d6 + 3) bludgeoning damage.

Reactions

Engine of Pain. Immediately after a creature within 5 feet of the hammerer hits it with an attack roll, the hammerer makes a Hammer attack against that creature.

Lore

Creative duergar engineers have built numerous war machines, including some that can be fused with a duergar. Such a duergar-machine hybrid is fueled by the duergar's psionic energy, and the duergar inside the machine can psychically channel pain into power when attacked.