Water web, oil slick, whatever
What is to stop you creating two identical set of labels, and then off camera weighing the packs and either just keeping the heavy ones and sending out the light ones, or replacing the heavy ones with light ones with the same artwork from another box
When they deal combat damage to an opponent, that player loses one life and mills a card, and then you gain one life and scry 1
A fully decked-out Commander mana base can easily be a few hundred dollars before considering the rest of the cards
I don't want to think how much money this cost me, but I finally did it
You know the ones: Gloomlake Verge, Blazemire Verge, Floodfarm Verge, Hushwood Verge, and Thornspire Verge