Destroyer (5e Creature)
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Gargantuan construct, chaotic evil
Saving Throws Strength, Constitution, Intelligence
Charge. If the Destroyer moves at least 20 feet straight toward a target and then hits it with a Bite attack on the same turn, the target takes an extra 4 (1d8) bludgeoning damage. If the target is a creature, it must succeed on a DC 14 Strength saving throw or be knocked Prone.
Legendary Resistance (3/Day). If the Destroyer fails a saving throw, it can choose to succeed instead.
Release Probes. Whenever the Destroyer takes 35 or more damage on a single turn and is not reduced to 0 hit points, it releases a single probe from its body within 5 feet of itself wherever it was struck. Probes released in this way are Small unaligned constructs, with 10 hit points, an AC of 12 (natural armor), immunity to all the conditions and damages the the Destroyer is immune to, a Strength, Dexterity, Constitution, and Wisdom of 10, a Intelligence and a Charisma of 2, and a flying speed of 25 (no walking speed). A probe is hostile towards all creatures the Destroyer is currently hostile towards and can attack with a weaker version of the Destroyer's Death Laser (Ranged Weapon Attack: +0 to hit, range 20/40 ft., one target. Hit: 5 (1d10) lightning damage). All active probes make their actions immediately after the Destroyer's turn. If the Destroyer is killed, all active probes' turns replace the Destroyer's. If the Destroyer retreats, all active probes will use their speed (if necessary) to follow it.
Tunneler. The Destroyer can burrow through solid rock at half its burrow speed and leaves a 10-foot-diameter tunnel in its wake.
Multiattack. The Destroyer makes either one Bite attack and one Tail attack, or 3 Death Laser attacks.
Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 32 (6d8 + 5) piercing damage. If the target is a creature, it is Grappled (escape DC 17). Until this Grapple ends, the target is Restrained, and the Destroyer can't bite another target.
Tail. Melee Weapon Attack: +8 to hit, reach 15 ft., one target. Hit: 21 (5d6 + 4) bludgeoning damage.
Death Laser. Ranged Weapon Attack: +6 to hit, range 50/100 ft., one target. Hit: 15 (2d12 + 2) lightning damage.
The Destroyer can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The Destroyer regains spent legendary actions at the start of its turn.
Attack. The Destroyer makes 2 Death Laser attacks.
Move. The Destroyer moves up to half its speed.
One of the three legendary Mechanical Bosses, the Destroyer resembles a giant robotic worm. Like its fellow Mechanical Bosses Skeletron Prime and the Twins, the Destroyer's body is forged from bright silver hallowed metal. It consists of many identical segments, with two circular protrusions designed for mobility and a silver-colored probe with a single red mechanical eye, encased inside the segment to be released upon impact. On one end of its lengthy body is a pointed tail, and on the other is a head with a large, red, rectangular, cyclopean eye and two pairs of great tusk-like teeth. It resembles a longer, robotic version of the Eater of Worlds, but the two are unrelated. Along with the other Mechanical Bosses, the Destroyer was designed by the Lunatic Cult and built by the enslaved Mechanic as a cybernetic enhancement for Cthulhu's broken body, specifically, his destroyed spinal chord. Yet untethered in Cthulhu's back, the Destroyer tunnels free, called to the electronic signal released from a magical, worm-shaped beacon, forged of metal, spinal flesh, and trapped souls of the unholy. To those daring (or foolish) enough to encounter the beast, it will dig circles around them, literally, and blast them away with Death Lasers, defending itself with its allied probes. It is said that whenever the Destroyer is near, one can feel vibrations from deep below...