At the bottom rank of our Mythical Creatures List we have the Orc.
The Orc is a humanoid often depicted with its typical signature greenish skin, with strong physical similarities to man, yet a few distinct physical features. They are significantly taller than man averaging about a '1 or so higher, and they have very muscular builds and a very broad frame. In many cases they are depicted with horns or tusks, and usually have little or not hair, although in more civil portraits they do have similar natural hairstyle to typical medieval man. Orcs have often been portrayed as savage and fierce, displaying spouts of aggression and blood-lust for brutal combat. However in recent media and cinema culture, Orcs have taken a role more so of honorable warriors who uphold strong a sense of honor and courage, coupled with their fearlessness and love for battle.
Orc origins in any story involving them, hold almost identical similarities; in almost every case, Orcs seem to be a foul spawn of an evil overlord, destined for malicious and savage practices. Though created as sturdy warriors, Orcs always seem to be the pawn for a higher evils bidding. In most cases, Orcs go on filling their niche and mindlessly abide to higher evils. In some isolated stories and media however, Orcs have been depicted as breaking away from such control, and going on to prove their worth as honorable beings.
Orcs were probably one of the first to appear on cinema in post WWII era from our Mythical Creatures list, in the Lord Of the Rings series. In this setting, they take on their primitive and most basic Niche, as the mindless pawn of evil. However, many would agree that the most popular Orc image today would be from the video game World of Warcraft. If it weren't for World of Warcraft, the Orc would not even have come close to our Mythical Creatures List. In this setting, Orcs do play their initial stereotype at first, but as the Warcraft story progresses, it reveals that Orcs, when free from the reins of chaotic overlords, at times actually appear more humane and honorable than humans themselves.
I firmly believe this creature will hold its own ground for the coming decades as a popular on any Mythical Creatures List, especially due to the explosive publication it has enjoyed after the launch of World of Warcraft. Even though I could not place it higher on the Mythical Creatures List simply because of its popularity, I believe the Orc has made the most colossal of jumps on even the most popular mythical creatures list over any other Mythical creature in the past decade.