Strong Back 
Enchantment — Aura
Enchant creature
Equip abilities you activate that target enchanted creature cost 
less to activate.
Aura spells you cast that target enchanted creature cost less to cast.
Enchanted creature gets +2/+2 for each Aura and Equipment attached to it.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL