staryu pokemon card POKÉMON GAME sv4a 221/190 S Water Recover Discard a Water Energy card attached to Staryu and remove 4 damage counters from Staryu (all if there are less than 4) Staryu - Pokémon 151 (MEW)

Nasty I know and pretty good at all of the game-winning since you can kill folks fast no matter their starting or current life total

This goes to show that a card can be banned for synergizing too well with a deck as a whole and not a single card in particular

Sure, some creatures are more useful than others, and you're limiting the number of times you can pull off various graveyard shenanigans, but if this isn't a major focus of your deck, who wouldn't like, say, a free Craterhoof Behemoth for a turn

But milling yourself and cycling both rip through your deck to the point where you can draw your namesake card with high enough consistency to make it worth it