Who Goes There?

Devoid (This card has no color.)
Target creature's controller sacrifices it, then
creates a token that's a copy of it, except it's
colorless, an Eldrazi Shapeshifter in addition to
its other types, and it has "at the beginning of
your upkeep, this creature deals damage equal to
its power to you."
This thing doesn't want to show itself, it wants to hide inside an imitation.