Arcano, Hellish Inferno

As an additional cost to cast Arcano, Hellish
Inferno, sacrifice any amount of creatures with
total power 7 or more.
When Arcano, Hellish Inferno enters the
battlefield, exile target creature card from a
graveyard. You may pay {x}{b/r}{b/r} and cast that
card from exile without paying it's mana cost,
where X is that cards converted mana cost or
your life total.