One real serial killer who is known to have worn a gas mask is Anthony Sowell. He was an American serial killer who operated in Cleveland, Ohio, and was active in the late 2000s. Sowell was known for luring women to his home, where he would sexually assault and murder them. He was arrested in 2009, and when police searched his home, they discovered the remains of multiple victims.
Sowell reportedly wore a gas mask to cover his identity and to deal with the foul odor emanating from his home, where decomposing bodies were found. He was convicted in 2011 and sentenced to death.
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