Archimonde’s Felsteel Anihilator
Archimonde’s Felsteel Anihilator was the WOW TBC Gold only mythical mount that I remember being "original at the time". The new Sylvanas mythic Mount is also a new type.
I'm assuming that a recolour often is a swap of textures? Im not certain as far as the definition. It certainly is far easier to color change than other items in that they simply need to make use of a slider alter the color of it and then call it a day.
This is why it's so difficult to observe so many cheap Burning Crusade Classic Gold armors simply being recolored. You could easily place an intern on it and they'd generally be good. Recolors should always be a slider option that players have access too..