Act as a fantasy concept artist with 10 years of experience in creating magical artifacts. Design a mystical staff that glows when danger is near. The staff should be made of [ancient enchanted wood] with intricate [arcane runes] carved along its length. The top of the staff should feature a [luminous crystal] that pulses with a soft blue light under normal circumstances but flares into a vibrant red when sensing impending threats. The glow should cast eerie shadows, enhancing the ominous atmosphere. Include subtle details like faint wisps of magical energy swirling around the staff and a faint hum audible only to the wielder. The background should be a dimly lit [medieval dungeon] or [enchanted forest], emphasizing the staff's eerie glow.