Brawl Not Legal Vintage Legal Timeless Not Legal Commander Legal Pauper Not Legal Oathbreaker Legal Penny Legal Toolbox Buy This Card Notes and Rules Information for Polymorph: If there are no creatures in the players library, then the target creature is still destroyed, you see all the cards in that players library, and then they shuffle and continue play
But if you want mana quickly, now, without jumping through hoops, this is where you'll stop
For the cost of each color mana, you can give your creatures a ton of useful keywords haste, trample, and lifelink and an additional combat phase
Are they the most efficient versions of those spells (furthest down the curve), showing you the most cards (options) for the least mana
I have now tested the companions fairly extensively in numerous types of cube both with and without rule changes
It's okay if any of them are already tapped, and it's okay if any of them are controlled by someone other than the defending player