The Cryptard of Harrow's Gate

Deathtouch, Fear, Flash

When this creature enters the battlefield, create a Legendary Artifact called "The Sack of Unknowable Horrors".

{x}, As an additonal cost to cast this spell you may pay X, if you do place the top X cards of your library face down on the battlefield, on an opponents upkeep they roll a d6, on odds they flip a target facedown card you control.

"Uuuh.. uh.. uuuh.. dearest apologies, may I?"