Leira, Lady of Mists

Hexproof
As long as your devotion to blue and black is less
than seven, Leira isn't a creature.
At the beginning of your upkeep, create a token
that is a copy of target creature an opponent
controls. It gains haste until end of turn. Exile it
at the beginning of your next end step.
"You say it's just an illusion, but when its teeth sink
into your flesh they'll feel real enough."