Quintessential Katana
From Teenage Mutant Ninja Turtles set
Quintessential Katana
Artifact — Equipment
Equipped creature gets +1/+1 and has "Whenever this creature deals combat damage, untap it and you gain 2 life."
Whenever a Ninja you control enters, you may attach this Equipment to it.
Equip
(
: Attach to target creature you control. Equip only as a sorcery.)