Praxis as you know it, but with a lot of card draw. Distillation works well with mana dorks that can't attack anyway, while Grodov's Stranger + Predator's Instinct allows you to ramp, draw two, shuffle a void and kill a unit immediately; pretty busted. Since Stranger plays undepleted power you only need 6 power for it too.
Arcanum can give Stranger charge for immediate draw as well, also works with Vanguard, and generally making stuff cheaper is pretty useful.