Trollskull Manor

If this card would enter the battlefield, sacrifice
an untapped Plains, Island, Swamp, Mountain,
and Forest instead. If you do, put this card onto
the battlefield. If you don't, put it into its
owner's graveyard.
{t}: The next spell with "#0", "#1", "#2", "#3",
"#4", "#5", "#6", or "#7" in its name that you
cast costs {w}{u}{b}{r}{g} less to cast. This effect
reduces only the amount of colored mana you
pay.