Heartfelt Song, Loronerol

: 1, choose a face up Song from your Order Zone, and sing it. (Activate the Song's ability, and turn it face down after that ability resolves) :When this unit attacks, if you have two or more face down cards in your Order Zone, choose a face up Song from your Order Zone, sing it, and until end of that battle, your opponent cannot call sentinels from hand to .