So if your opponent doesn't play a creature by turn two, you can make them discard their entire hand on the play. In green? (This should probably be 6cmc at least.)

If you are playing this on turn 3, then most likely you don't have too big of a creature either. I agree it should be more than 3 CMC, but probably less than 6. Perhaps 5?

Huh. I wonder what cost "All players discard their hands" should be. Created Cycle of Winter to find out.

But this is actully really hard to cost. Green starts getting seriously beefy creatures at cmc4+ and they just get beefier. Other colours don't ever catch up; so it's always going to be better for you than them even if they know it's coming. So higher costs means you're getting even more advantage from this! But, then again, the differential between "I draw 6 you draw 4"is a lot bigger than "I draw 3, you don't get any" so yeah, the sweetspot is a bit higher than this.

Love the general idea though. Great card.

(Actually, black has a few cheap stompy demons with severe downsides, it might be able to)

It was a sketch card-- would it be better if it was more like Windfall? Or if it took into account creature cards in graveyards? I'm okay pushing it to 4 or 5. I wanted to see if I could create a green flavored wheel effect so this was the first swipe. I'm also thinking maybe have it draw cards equal to the number of basic lands you control. That's aggressively asymmetrical in a way that pushes people back towards simple mana bases. Just ideas-- let me know what you guys think!