Ancient Whirlpool can be devastating against a deck that relies on one or two heavy hitters, as it can shut down their ability to counter
If you just want to open packs, please, for the love of the Grand Line, buy a standard reprint box and save yourself about 90% of the cost
Kida - Crystal Scion (Legendary, #160) has ward and card advantage abilities that make it viable in control shells
Its especially good with another double-black card, Rankle, Master of Pranks, since the discard adds up and it gives you a free body to sacrifice
Think Furnace ReinsFurnace Reins, Act of TreasonAct of Treason, and Song-Mad TreacherySong-Mad Treachery - which doesn't even cost you a nonland slot