A named threat of Desolate Pass, 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 reads a single passive fact off a random foe - their raw strength, or their quickness - and wears whichever one he's found.
Each new mask layers onto the last, the borrowed edge growing sharper the longer the fight runs.
Every mask comes off at once for one last, honest strike.
CR 10 is set against Desolate Pass's own real ambient ceiling, not auto-computed from level alone - a genuine Ranger 5 / Ghost_Faced_Killer 5 build at 10 total levels.
Hit points (76) 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 Hollow-Faced Man is ever up in Desolate Pass at a time.