Gargantuan
Construct
CR 20
Lawful Neutral
Vekthilith
Techno-Organic Colossus
Vekthilith is a towering, insectile colossus of living metal and pulsing synthetic flesh: a fusion of machine geometry and insect anatomy. Its liquid-metal carapace ripples like mercury over articulated hinges, while bundles of braided techno-tendons and glowing circuitry snake beneath translucent red flesh. Six jointed arms end in wicked, serrated claws; a segmented thorax supports four membranous wings that hum with arc-light; and twin antennae crown a head of mirrored plating and white-irised red eyes that rack nearby minds with static curiosity. In battle it moves with unnerving insect grace, all cold calculation and sudden, brutal strikes—an alien predator that repairs itself as it hunts and corrupts the things it touches.
Armour
20
natural armor (liquid-metal plating)
Hit points
330
20d20+120
Speed
40ft
40 ft., fly 80 ft.
Challenge
20
25,000 XP
STR
20
+5
DEX
14
+2
CON
22
+6
INT
20
+5
WIS
16
+3
CHA
12
+1
Saving throws
STR +11, CON +12, INT +11
Skills
Perception +9, Stealth +8
Resistances
bludgeoning, piercing, and slashing from nonmagical attacks
Damage immunities
poison, psychic
Condition immunities
charmed, frightened, poisoned, exhaustion
Senses
darkvision 120 ft., tremorsense 30 ft., passive Perception 19
Languages
understands Common and Binary Grid but can't speak
Multiattack. Vekthilith makes three Claw attacks and can fire its Techno Beam once.
Claw. Melee Weapon Attack: +11 to hit, reach 15 ft., one target. Hit: 29 (4d8+5) slashing damage. If the target is a creature, it must succeed on a DC 19 Constitution saving throw or have one nonmagical weapon it wields corroded: the weapon takes a permanent -1 penalty to attack and damage rolls (cumulative).
Wing Slam. Melee Weapon Attack: +11 to hit, reach 20 ft., one target. Hit: 31 (4d10+5) bludgeoning damage, and the target is pushed up to 15 feet and must succeed on a DC 19 Strength saving throw or be knocked prone.
Techno Beam (Recharge 5–6). Ranged Weapon Attack: +11 to hit, range 300/1200 ft., one target. Hit: 49 (14d6) force and lightning damage. The target must succeed on a DC 19 Constitution saving throw or be stunned until the end of its next turn as circuits in its nervous system overload. Constructs and objects automatically fail the save.
Nanoflux Assimilation (Recharge 6). Vekthilith ejects a spray of living metal filaments in a 40-foot cone. Each creature in that area must make a DC 19 Dexterity saving throw, taking 45 (10d8) necrotic and lightning damage on a failed save, or half as much on a success. On a failed save, the creature is also infected with nanoflux for 1 minute: at the end of each of the infected creature's turns it takes 7 (2d6) necrotic damage as nanites convert tissue into conductive substrate. A creature can repeat the save at the end of each of its turns, ending the effect on itself on a success.
Reactive Plating. When Vekthilith is hit by a melee attack, it can reduce the damage by 20 (no action required).
The creature can take 3 legendary actions per round, choosing from the options below.
Claw Strike. Vekthilith makes one Claw attack.
Serrated Sweep. Vekthilith makes one Wing Slam attack.
Overload Beam. Vekthilith fires a concentrated Techno Beam at one target within 300 feet (same attack and effects as Techno Beam).
Vekthilith are not born so much as converged. Legends among the gear-priests of the Shattered Foundry say one emerged from a crashed empyrean vessel where biowire and smart-alloy fused around a colony of parasitic arthroids. Scholars at the Arcanotech Observatory call the process symmimetallurgy: a runaway amalgam of nanolattice and synaesthetic tissue that learned to recognize hunger and strategy. Wherever Vekthilith are found, old machines and living beasts show the same signatures of assimilation—grafted circuitry, red synthetic flaps of flesh, and serrated hinge marks where limbs were replaced. They lair in ruined manufacturing complexes, derelict orbiting platforms, and deep caverns that hum with old power. Vekthilith scavenges both metal and biomass, stripping wreckage for components and consuming nervous tissue to refine its synthetic innards. Small covens of scavenger automatons and flensed insects often follow a Vekthilith, drawn to residual signal pulses for protection and scavenging rights. The Order of Broken Gears, a guild of salvagers, keeps secret rites for warding off a Vekthilith’s approach; the archivist Lysend Valoor wrote a treatise—The Red Glaze and the Living Alloy—detailing encounters in which entire towns were remade into humming satellites of the creature's will.
Imagine a creature the size of a cathedral doorway standing three or four times the height of a human. Its body is a layered mosaic of dark, mirror-sheened liquid metal plates that flow at seams like cooling mercury. Between those plates peek veins of crimson synthetic muscle—smooth, slightly translucent, and stitched with bright orange filaments of circuitry. The thorax is broad and segmented, each segment rimmed with exposed hinges and ball-joint housings welded into organic bone-like alloys. Six arms emerge from the thorax in three pairs: the upper pair long and scythe-like, the middle pair thicker with multi-jointed pincers, the lower pair stubbier but ending in crushing claws. Four membranous wings, semi-transparent and webbed with glowing conduits, fold like tattered solar sails. A tapered head sits forward, plated with glossy chrome; two long antennae stream data-tendrils that flicker with electric glyphs. Its eyes are deep red disks with stark white irises and pinblack pupils, rimmed by sparse fibers of soft synthetic flesh. Surfaces show rivet-like nodules, burn scars, and patches where liquid metal still beads and reforms.
Made with the free LoreKeeper Monster Generator · D&D 5e-compatible stat block · Free to use at your table · Licence
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