I think playing 16 is legitimately a strategy in some of the cubes posted, too - even when the extra card will often be another basic, if you specifically need X colored sources, and when running out of resources is a factor even if decking doesn't lose you the game...I made the original cheating comment as a total joke, hur all this time I assumed your deck should be exactly 15 cards, but it’s the cube size that’s set (and 72). So at running Yorion requires you mess up your spells to land ratio. That’s actually funny XD