The Maru Virus was a bio-chemical agent based off of Soviet combat drugs from the Cold War that had been weaponized by Sear Group, worshippers of Ares. It floods the body with adrenaline and impairs reasoning, making the victims lash out and kill everyone around them until they are either stopped or the chemical kills them. The chemical can be inhaled or ingested, making gas attacks and water tampering equally viable.
On behalf of who they thought to be Ares (truly his sons Deimos and Phobos masquerading as him), the Sear Group aimed to release the Maru Virus on Tokyo, Cairo, Moscow, Munich, New York City, and even the United Nations Building, but were stopped through the efforts of A.R.G.U.S., Diana of Themyscira, and her Lasso of Truth, which could help negate the toxin's effects.
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