Avacyn's Collar, the Symbol of Her Church 

Artifact — Equipment
Equipped creature can't attack, block, or transform, and its activated abilities can't be activated.
Shackle (
: Attach to target creature you don't control. Shackle only as a sorcery.)
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyNOT LEGALvintageNOT LEGALcommanderNOT LEGAL