You might cast Reforge the Soul and cascade into Whispering Madness, then cast Chain of Vapor which cascades into Wheel of Fate, all while your Waste Not bombards you with zombies / mana / card draw and your opponents watch with disgust at your amazing luck
This can come in the form of Assault Formation effects that reverse how your combat damage is dealt, or maybe Phenax, God of Deception using toughness to mill opponents
Most are at least nominally colourless, and strong in virtually any deck
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DREDGE Another common top pick for most broken mechanic is the perennial graveyard enabler