This creature looks like a larger version of a normal wasp with a jet black body and reddish eyes.
Vapor Wasp CR 4
Vapor wasps are not aggressive creatures and generally avoid combat unless threatened or unless the hive is threatened. Creatures wandering within 100 feet of a vapor wasp hive are harassed but almost always left alone. If attacked, or if the hive itself is threatened, the vapor wasps attack relentlessly, using their poisonous sting to fell their opponents.
Environment temperate forests
Organization solitary, swarm (2-5), or nest (11-20)
Vapor wasps resemble giant wasps in all respects. In some rare species their coloration seems to vary slightly (a blue stripe on the abdomen is the giveaway). Vapor wasps construct their nests above ground and most often in forested areas. They rarely build their hives in mountains, deserts, or cold climates.
A vapor wasp hive is for the most part indistinguishable from an ordinary giant wasp hive.
Vapor Wasp from the Tome of Horrors Complete, Copyright 2011, Necromancer Games, Inc., published and distributed by Frog God Games; Author Scott Greene.