Bing's AI Is A Bit Confused

The prompt "snowy, irradiated wasteland with crumbling, burning Roman-style architecture, clouds of toxic green gas, zombies (some of which are wearing gas masks, some not), and an army of fire-breathing dragons and tentacle monsters in the blood-red sky" generates exactly what it is supposed to but once you add "skulls and bones littering the ground", it starts generating rainbow happylands!