It can deal X damage to any target you choose, which is incredibly useful as both a removal spell and something to finish off a player who has too many creatures to defend with
It verges towards the generic, but you cant deny the power of a Coastal Piracy variant that proliferates
And even if you aim to extend the game far beyond the next turn, youre almost always trading up on mana while remaining even on cards (and, in fact, seeing deeper into your library)
Then you would steal the scariest threat on the table or you could take your opponent's commander, if their deck relies on it heavily, effectively neutering them until they can remove it and recast the commander
Consistency often yields better results than sporadic chases after giant headline deals with demanding conditions
The Power Nine is one such bit of jargon, and that vague status alone goes a long way to setting apart a group of already desirable cards as something eternal and legendary