Believe in the Cleave 
Instant
Believe in the Cleave costs 
less to cast for each attacking creature you control.
Target creature gets +1/+1 and gains double strike and trample until end of turn.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyNOT LEGALvintageNOT LEGALcommanderNOT LEGAL