Adamantine Obliterator (5e Creature)
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Gargantuan construct, neutral
Skills Perception +6
Immutable Form. The obliterator is immune to any spell of effect that would alter its form.
Limited Magic Immunity. The obliterator is immune to any spell of 4th level or lower.
Magic Resistance. The obliterator has advantage on saving throws against spells and other magical effects.
Magic Weapons. The obliterator weapons attacks are magical.
Siege Monster. The obliterator deals double damage to objects and structures.
Twin Construct. Each head acts on different initiatives.
Multiattack. The obliterator makes two slam attacks and one pincer attack.
Slam. Melee Weapon Attack: +18 to hit, reach 20 ft., one target. Hit: 48 (7d10 + 10) bludgeoning damage.
Pincer. Melee Weapon Attack: +18 to hit, reach 30 ft., one target huge or smaller. Hit: 28 (4d8 + 10) slashing damage, the target is grappled (escape DC 21). Until this grapple ends, the target is restrained, and takes 10 (2d6 + 3) slashing damage at the start of the relevant head's turn. The obliterator has three pincers per head, each of which can grapple one target.
Fire Breath (Recharge 5-6). The obliterator exhales fire in a 90-foot cone. Each creature in that area must make a DC 24 Dexterity saving throw, taking 91 (26d6) fire damage with three pincers free, 62 (18d6) with two free, 30 (9d6) with one free, on a failed save, or half as much damage on a successful one. With all three pincers active the obliterator is unable to use its fire breath.
A construct created using a ludicrous amount of iron and multiple uses of the wish spell, the adamantine obliterator is possibly the most devastating weapon ever created, save for one flaw. The construct's two heads are completely independent of one another, leading to it being prone to being easily disoriented. Due to this only one was ever created, and promptly locked away after only one battle where it was easily deafened by simple trickery.