Cloud defeats Sephiroth, seemingly killing him, but is heavily injured in the attempt
As long as the player has a card already in play matching the required criteria, then theyre able to play another - usually more powerful - card on top of it for less ink than it would cost to play it otherwise
And if you cast it from your graveyard with flashback, you also get to discard your hand and draw four cards to give you a full reload after the carnage
You cant plan around these cards, as they arent always there, but they show up frequently enough to mess up your game plan
Multiple early Sahagin in particular will just outrace a majority of decks, and its not actually difficult to find expensive noncreature spells since the set is built with this theme in mind
A 7/7 is tough to kill, but what if your opponent has untapped lands available to potentially play a combat trick