Demand for Conflict

Whenever a legendary creature attacks, you
may pay {2}. If you do, you may reveal a Planeswalker, Phyrexian, or Eldrazi spell
from outside the game and put it into your
hand. As an additional cost to activate this ability, create a reason why this spell is crucial to the plot of the current game.
You cannot reveal the same spell type
more than once this way.