Sources
CR
Type
Size
Alignment
Movement

Abigor

Large Fiend (devil), Lawful Evil

Armor Class 22 (natural armor)
Hit Points 337 (27d10 + 189)
Speed 30 ft.
STR
27
+8
DEX
14
+2
CON
25
+7
INT
20
+5
WIS
16
+3
CHA
16
+3
Saving Throws STR +15, INT +12
Skills Athletics +22, History +12, Insight +10, Intimidation +17, Perception +10, Survival +10
Damage Resistances cold; bludgeoning, piercing, slashing, from nonmagical attacks that aren't silvered
Damage Immunities fire, poison
Condition Immunities Poisoned
Senses darkvision 120 ft., passive Perception 20
Languages Celestial, Common, Draconic, Infernal, telepathy 120 ft.
Challenge 22 (41,000 XP)

Traits

Devil's Sight. Magical darkness doesn't impede Abigor's darkvision.

Magic Resistance. Abigor has advantage on saving throws against spells and other magical effects.

Actions

Multiattack. Abigor makes four attacks using its Warhammer, Throwing Hammer, or a combination of the two.

Warhammer. Melee Weapon Attack: +15 to hit, reach 5 ft., one target. Hit:17 (2d8 + 8) bludgeoning damage plus 3 (1d6) thunder damage.

Throwing Hammer. Ranged Weapon Attack: +15 to hit, range 30/60 ft., one target. Hit:17 (2d8 + 8) bludgeoning damage plus 3 (1d6) thunder damage. Hammers thrown this way fall and stick into the ground after hitting their target and a new hammer appears in Abigor's hand.

Thunderous Slam (Recharge 5–6). Abigor causes all its hammers left on the battlefield to bristle with thunderous energy, exploding outwards with a roar. All creatures within a 10-foot-radius sphere centered on each hammer must make a DC 22 Constitution saving throw. Targets take 26 (4d12) thunder damage on a failed save, or half as much damage on a successful one. If a creature is within multiple spheres, it must make the save multiple times, taking damage from each source.

Legendary Actions

Throw Hammer. Abigor makes a Throwing Hammer attack.

Call Thunder (Costs 2 Actions). Abigor targets a hammer that it can see within 60 feet to let out a thunderous roar. Creatures within a 10-foot-radius sphere centered on the hammer must make a DC 22 Constitution saving throw, taking 26 (4d12) thunder damage on a failed save, or half as much damage on a successful one.