A Large Heavy Extra-terrestrial Creature Slowly Crawling Through A Narrow Met...
A large heavy extra-terrestrial creature slowly crawling through a narrow metal ventilation duct, Irregular scraping claws, heavy body dragging across sheet metal, hollow metallic thumps, vibrating duct panels and occasional sharp rattles, Movement starts distant, gradually approaches, then stops abruptly, Claustrophobic enclosed metal acoustics, realistic physical weight and movement, Isolated sound effect, no voices, growls or music
