Kayla's Music Box 
Legendary Artifact
, 
: Look at the top card of your library, then exile it face down. (You may look at it any time.)
: Until end of turn, you may play cards you own exiled with Kayla's Music Box.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL