Equipped creature gets +2/+2.
Whenever a creature dealt damage by equipped creature this turn dies, return that card to the battlefield under your control. Attach this Equipment to that creature.
Equip

Scythe of the Wretched needs to equip your creature when the other creature goes to the graveyard for the ability to trigger, but it doesn't matter whether the Scythe equipped your creature when the damage was actually dealt.