Doomsday Cesario was an arms dealer based in Paynesdown District during the City of the Saved Civil War.
A group of peace activists infected Cesario with a potentially fatal nanopoison - which he had been selling - in order to blackmail him into stopping selling weapons and giving vital information on his customers. Cesario hired Laura Tobin to uncover who had poisoned him, but she was associated with the activists and delivered their ultimatum to him. (PROSE: A Hundred Words from a Civil War)