He is snarky, condescending, arrogant, and cruel. Despite his power, however, Heimdall is somewhat cowardly and fearful of people of greater power, He proves to be wound up extremely tight and distrustful of everyone around him due to this irreplaceable position as Odin's mind-reader. His foresight is something he held in great confidence as it was the one power that made him untouchable, above everyone else.