Glyph of Warding

When Glyph of Warding enters the battlefield,
scry 3 and choose target instant from your hand,
top of your library, or graveyard with converted
mana cost X and exile it. When one or more creatures deals combat damage to you, you can sacrifice Glyph of Warding. If you do, cast target
spell without paying its mana cost. If you paid {b}, destroy target creature that dealt damage to
you this turn when you sacrifice Glyph of
Warding. If you paid {w}, gain 5 life when you sacrifice Glyph of Warding.