Combines brown adipose tissue expansion from arctic mammals with countercurrent heat exchange vascular modifications and enhanced subcutaneous insulation. The user becomes functionally immune to hypothermia in temperatures above -40°C without protective clothing. The modification increases basal metabolic rate to fuel internal heat generation, requiring significantly higher caloric intake. The user's skin runs slightly warm to the touch — noticeably so in cold weather, when condensation sometimes forms on their skin from the temperature differential. Gravemoss Biofoundry developed the suite for deep-infrastructure maintenance workers in GLMZ's exposed upper structures, where wind chill and industrial cold exposure are constant hazards. The modification has become popular among Shelf residents who can't afford consistent heating.