A named threat of The Labyrinth, encountered rarely and never in numbers - real Dungeons & Dragons statistics, no auto-computed shortcuts.
Layered on top of the module's own combat AI, which still picks targets and positioning. The fight below moves through real hit-point-gated phases; every save DC and attack bonus computes from the stat block above at runtime.
He cannot be knocked down, not once, not ever.
A slab of real rubble rises wherever the nearest foe is standing - and stays there for the rest of the fight, redrawing the maze under everyone's feet.
A wide slow-and-entangle answers whoever's left standing in the walls he's built.
CR 10 is set against The Labyrinth's own real ambient ceiling, not auto-computed from level alone - a genuine Construct 7 / Fighter 3 build at 10 total levels.
Hit points (82) follow this project's own average-hit-dice convention, and every save/attack bonus derives from the ability scores above at runtime - nothing here is hardcoded past the phase gates themselves.
Boss-flagged (bypasses the drop-rate roll, two loot-generation passes) and gated to a single spawn - only one The Warden of the Unwound Way is ever up in The Labyrinth at a time.