Enchantment
Whenever
an
opponent
attacks
you
and/or
one
or
more
planeswalkers
you
control,
exile
the
top
card
of
that
player's
library.
You
may
play
that
card
for
as
long
as
it
remains
exiled,
and
you
may
spend
mana
as
though
it
were
mana
of
any
color
to
cast
it.
