Magatsu, Khan of Oblivion

You may pay 2 life for each generic mana needed
to cast Magatsu, Khan of Oblivion instead.
Menace, Deathtouch, Toxic 4, Devoid
If a permanent would enter a graveyard during a
combat phase, exile it instead, you may cast spells
and play lands this way. Spells cast this way cost
X, where X is their converted mana cost minus
their generic mana cost.