Pretty straight forward deck, it's huge right now but I'm sure it could be optimized pretty easily. Like other decks of this type it seeks to steal any decent threats, used them against the enemy and then sacrifice them for further gains. Early game you can attempt to flood the board with 1/1's.
Unfinished Business is one of the cards that has a lot of perks to it, it can kill a stolen minion and works great on anything with revenge or when you have a
Dark Return as the +5/+5 doesn't disappear at the end of the turn.