The body of the furnace is engraved with a Blood Sea Map. In the scroll, the blood sea churns, corpses rise and fall, countless twisted faces struggle, wail, and sink in the blood waves. These faces are male and female, old and young, some ferocious, some fearful, some in despair, some mad — each face was a life sacrificed when the pill furnace was cast.
On the two sides of the furnace hang human bone bells. As the temperature of the pill fire changes, they produce different sounds — sometimes like a baby's cry, sometimes like a woman's sob, sometimes like an old man's sigh, sometimes like a warrior's roar. The sounds change endlessly and are never repeated.
Three blood-red poisonous snakes coil around the three legs of the furnace, each as thick as an adult's arm, their heads raised, tongues flickering, eyes blood-red.
Whenever their master, the Red Robe Guest, is conducting alchemy, the three blood poison snakes spit out blood poison flames to boost the pill fire.
