Act as a dark fantasy concept artist with expertise in medieval weaponry and supernatural elements. Design a highly detailed, photorealistic image of a medieval executioner’s axe infused with dark energy. The axe should have a [WEATHERED IRON] blade, etched with [OCCULT RUNES] that glow an eerie [VIOLET OR GREEN] hue. The handle should be wrapped in [ANCIENT LEATHER], stained with age and use. The dark energy should manifest as swirling shadows or crackling energy around the blade, casting an ominous glow on a [DIMLY LIT STONE] execution block in the background. The composition should evoke dread and mystery, with faint mist or smoke enhancing the atmosphere. Pay close attention to textures, lighting, and the contrast between the axe’s brutal physicality and its supernatural aura.