Nightmare Lash 219/306 (Mirrodin)

Equipped creature gets +1/+1 for each Swamp you control. Equip—Pay 3 life. (Pay 3 life: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

NM - $4.10
LP - $3.30
MP - $2.50
HP - $1.70
DMG - $1.50