Magic players are nothing if not resourceful
Lets think about Monstrous Rage, a card thats in Standard
In Magic terms, Amethyst is closest by far to blue, with some elements of black
The Seventh Doctor card, showing Slyvester McCoy as the Doctor, features a much more complicated ability that has defending players attempting to guess whether the mana value of a card in the attacking players hand is greater than the number of artifacts they control
If you do, when this creature enters, create a 1/1 token copy of it.) Whenever you attack, choose one Create a 1/1 white Rabbit creature token that's tapped and attacking
Even tamer situations, like destroying a few random mana rocks or Oblivion Ring-esque cards makes it scary due to the huge mana advantage it provides