Underground, Undertale-inspired, fantasy world, dimly lit cave, eerie atmosphere, glowing mushrooms, ancient ruins, mysterious artifacts, abandoned laboratory equipment, old computers, dusty machinery, pipes, rusty metal doors, creepy ambient sounds, faint whispers, Papyrus, Sans, Toriel, Chara, Asgore, Royal Guard uniform, skeletal hands, blue and orange color scheme, warm lighting, cinematic composition, foggy mist, dramatic shadows.