You may have this creature enter as a copy of any creature on the battlefield, except it's an Illusion in addition to its other types and it has "When this creature becomes the target of a spell or ability, sacrifice it."

Illusion creatures you control get +1/+1 and have hexproof. (They can't be the targets of spells or abilities your opponents control.)

Flying When this creature becomes the target of a spell or ability, sacrifice it.

Counter target spell.

This creature can't be blocked.

({T}: Add {U}.)

+1: Draw a card. Target player mills a card. 0: Target player mills ten cards. −7: Any number of target players each draw twenty cards.