Enchantment — Aura
Strong Back
Enchant creature Equip abilities you activate that target enchanted creature cost {3} less to activate. Aura spells you cast that target enchanted creature cost {3} less to cast. Enchanted creature gets +2/+2 for each Aura and Equipment attached to it.
From Magic: The Gathering.
Exact printings
Open the interactive version on https://mythscribe.cloud/app/tcg/cards/cms6o2mx20nbppb1h14bvn5op.