Hexmage Depths is a blue-black combo/control deck which became popular around Pro Tour Austin 2009, right after the release of Vampire Hexmage in Zendikar. The Hexmage is used to remove all counters from Dark Depths and put a 20/20 indestructible flying Marit Lage token into play that will most likely deal lethal damage to the opponent in the next attack. Another very vital card in the deck is Urborg, Tomb of Yawgmoth as it has Dark Depths produce black mana, thus making it possible to combo out Marit Lage on turn 2 and swing for lethal on turn 3.
Paulo Vitor Damo da Rosa made it into the Top 8 of Pro Tour Austin 2009 with such a deck.