Suddenly your Leyline Bindings are answering two permanents, your evoke Elementals become super-charged double triggering when they enter the battlefield, your Fable of the Mirror-Breaker is making double the Goblin tokens, and this isnt even considering the possibility of actually building around Elesh Norn in some sort of ETB heavy Soulherder or Ephemerate blink shell
As you get closer to end of a game, where hands are emptier and answers are largely spent, finding a finisher like Tooth and Nail or Rise of the Dark Realms is generally a safe play, even if youll have to wait until next turn to cast it
These cards make a huge difference to what players can do and greatly limits their options, especially powerful cards such as Sabrini
I know its disappointing to lose your C-Sphinx when there could be shenanigans like you and someone else both having them, but you can see how everyone else in the game might not enjoy that quite so much
Banshee of the Dread Choir Though most forms of card advantage involve accumulating resources, often through drawing cards, denying your opponents resources can be just as effective