This is a blue and black deck. This one is all about control. This one has about half the creatures that the other 3 decks have but has many more instants and sorceries. This guild has an ability called "Surveil" which lets you look at X top cards of your library and either put then back in any order or put any into your graveyard. This is useful for lining up what you will draw. It also has a couple of counter spells and instants that like to be played on your opponent's turn.

In the next set, Ravnica Allegiance, this pairs well with:
Azorious (Blue / White)
Simic (Blue / Green)
Orzhov (Black / White)
Rakdos (Black / Red)