Melatonin Injector

Flash
When you cast Melatonin Injector, Inquire 2,
then tap all creatures your opponent's control.
Creatures tapped this way with power equal to or lesser than the number of face-down cards you
own in exile Don't untap during their controller's
next untap step.
No matter how otherworldy the threat, once it is understood it is subduable.