Envoy's New Horizon

Envoy's New Horizon cannot be countered.
Play this Only if "Envoy, The True Vision" is in
your hand.
Play "Envoy, The True Vision" from your hand
for no cost, Exile Any Planeswalker in play with
"Envoy" In it's name(As well as all inert Cards
underneath it) and Exile all Cards in play with
"Vision" in their name.