Boubouille at MMO Champion: The Dungeon Challenge Mode/Timed Runs introduced in Mists of Pandaria will reward players with new cosmetic armor sets for completing dungeons really fast! Mists of Pandaria finally introduces real models for belts! Those new belt buckles make some of the sets look amazing and you can see some of them on the sets below.
Season 12 PvP sets
Challenge Mode Transmog sets
See all of the challenge mode and hunter pvp sets at Challenge Mode – Armor Reward Models Preview on MMO-Champion.