Halas' captive astral dreadnought

This astral dreadnought was encountered by the Mighty Nein within the Folding Halls of Halas.

Appearance
This astral dreadnought was 20 to 25 feet on a side, though its silvery tail seemed to curl off into an impossible distance. It was shaped like a bulbous, muscular serpent with two thick arms ending in pincers. Its body was covered in spiky armored plates and hardened, veiny, pale flesh plates. Its face had a single eye with a horned brow and a 12-foot-wide mouth edged with hundreds of two-foot-long teeth. Halas Lutagran kept this astral dreadnought chained and blinded, with a lever controlling the opening and closing of its mouth, so that he could use the capacious demiplane within as a ritual chamber.

Skills and Abilities

 * Demiplanar Donjon: The Mighty Nein entered the dreadnought's mouth to find a demiplane that Halas had used.


 * Given that Halas kept a large platinum plate bolted over the dreadnought's eye, this astral dreadnought likely has the same ability as in Mordenkainen's Tome of Foes: creating an antimagic cone.

Trivia

 * Knowing that Vokodo had desperately fled from something in the Astral Sea, Fjord used Major Image to create an illusory, smaller-than-usual astral dreadnought to frighten Vokodo during their battle. Despite Fjord having to guess at what an active dreadnought sounds like, the illusion worked: Vokodo was chased around the lair.