Dark horror fantasy transformation, rat-man sorcerer mutating into a colossal insectoid abomination

dark horror fantasy transformation, rat-man sorcerer mutating into a colossal insectoid abomination, towering body covered in cracked chitin plates, multiple crooked limbs ending in hooked claws, mandibles dripping with black ichor, glowing red eyes burning beneath the hood, plague fumes leaking from between the plates, treasure chamber trembling around the creature, oppressive and terrifying atmosphere, cinematic realism --ar 16:9 --v 7