Nightmare Conjuring

Exile the top of X cards of target opponent's
library, mill the top X cards of all other player's
libraries, and create X 2/3 Black & Blue
Nightmare creature tokens with "Whenever this
creature attacks or blocks each opponent exiles
the top two cards of their library."
The merest touch of the otherworldly Planeswalker
upon the Dream Portal was enough to call forth
a pair of Living Nightmares. A whisper, a swarm.