This ability is so strong it enables a game-winning combo with an old artifact called Fist of Suns, allowing you to cast any spell from your hand for free
This was a close call, but I believe next on the list is Ring of Morrigan
Legendary Creature - Goblin Rogue Hammers of Moradin Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control
If so, which and how many - and where in the pile
Id built a Type II deck around annoying blue & red creatures which a friend of mine piloted to victory, then built a similar deck to face off against the PT-Chicago Tongo deck makers which gave them fits
By paying one generic mana, one black mana, tapping Cryptbreaker and discarding a card, its controller gets to put a 2/2 black Zombie creature token onto the battlefield