Apostle of the False Sacrifice

{u}{u}{b},{t},You may change the target of target
spell to Apostle of the False Sacrifice.
If Apostle of the Sacrifice becomes the target the target of a spell or ability, sacrifice it.
Retrace (You may cast this card from your
graveyard by discarding a land card in addition to paying its other costs.)
"The sacrifice is constant, but is unreal"