They have much more in common with each other than either do with Necropotence and although residing in fairly different decks for the most part are still eating into the amount the other is getting played
That is not just some minor detail
Rubinia has the ability to tap to steal a creature your opponent controls, letting you hang on to it for as long as you control Rubinia and she stays tapped
Its a toolbox that can let you run away with a game with a Time Warp, answer any (nonland) card type with Counterspell, Putrefy, or Krosan Grip, or win with a random Claim the Firstborn your control deck would never play (yes, I did steal a Stonecoil Serpent and win with itand yes, it was awesome )
As creatures die, they will set up a nice draw trigger later on
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