Wall of Replica

If you control Dark Seer you may cast this spell without paying its mana cost.
Whenever a creature attacks you, make a token
copy of that creature, except it's a 1/1 blue and
black Replica and has, "Sacrifice this creature at
the beginning of your next end step."
The Dark Seer, while unable to return to his natural
realm, can channel part of the prismatic wall with powerful strength of mind, sowing confusion amongst
enemy ranks.