Nadu, Winged Wisdom

The design mistake was granting the ability to every creature you control, then scoping the cap per creature rather than per player. Read in isolation, the trigger looks like a controlled value engine: target one of your creatures, reveal the top card of your library, drop a land or bank a spell, and do it no more than twice per creature each turn. The break comes from the multiplier. Every creature is a separate instance of that ability, so a board of dorks paired with any repeatable, free targeting effect (Shuko, an untap-and-retarget loop) turns each cheap interaction into a fresh reveal, and the lands landing on the battlefield untap and re-enable another round of targeting. What was meant to reward incremental combat and spot interaction instead assembled a deterministic draw-and-ramp engine that emptied your own library into your hand and battlefield, then closed with a payoff like Thassa's Oracle.

That loop got the card banned in Modern within months of its release, one of the faster competitive removals of the modern era, and it drew the same scrutiny in Legacy. The 3/4 flying body and the "only twice each turn" clause read like restraint, but the cap counts per creature, not per player, and that single scoping choice is the whole story: a limit that scales with your board is not a limit at all. It stands now as a reference point for how combo emerges not from one overpowered line of text, but from an ability template that quietly stacks across a battlefield.