Wikipedia
KGBeast
KGBeast (Anatoli Knyazev) is a fictional character, a supervillain appearing in DC Comics. The character first appeared in Batman #417 (March 1988) as an adversary of Batman.
KGBeast's civilian identity appeared in Batman v Superman: Dawn of Justice, in which he was portrayed by Callan Mulvey, and during the second season of Arrow, in which he was played by David Nykl.