Cards like Brutal Hordechief, Skyknight Vanguard, and Krenko, Tin Street Kingpin spiral out of control when you double those juicy triggers

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It smooths out your draws, helping you to filter away unwanted cards and find what you really need
Or rather, there is no system to put out, but it will be effective until the next time Does Konmai have a grudge against this card
Depending on supply, this new Box Topper might just fill that role, but that currently remains to be seen
The final big proliferate-friendly card I'd recommend is Tezzeret the Seeker, which can find your important artifacts more efficiently than the other tutors can, plus it also acts as huge ramp if you've got an Everflowing Chalice or Empowered Autogenerator on the battlefield