Artorias, The Abysswalker

Partner with, "Sif, Guardian of The Grave"
(When this creature enters the battlefield, target
player may put "Sif, Guardian of The Grave"
from their deck into their hand then shuffle.)
Double Strike, Shroud (This creature cannot
be the target or spells or abilities)
While this creature is on the field creatures your
opponant controls cannot be unblockable.