Oath of Ashiok

When Oath of Ashiok enters the battlefield, exile
up to five cards from any graveyard.
Whenever a creature or planeswalker you
control is targeted by a spell or ability an
opponent controls, you may play a card exiled
with Oath of Ashiok and you may spend mana
as though it were mana of any color to cast
that spell.
Our own grim tale.