The abnormal spawn that Bruno had to get rid of wasn't the only one. All over the world, there would at least be one city to be within the terror of an abnormally powerful monster.
Powerful monsters that didn't correlate with any of the NPC's of video games… Maybe a slim chance for some resemblance, however, if it did indeed look alike to an NPC, it would either be a lookalike of a boss level NPC that is not supposed to appear early game, or a lookalike of a big but weak mob NPC that is supposed to be weak.