Leonardo's Technique (Showcase) [Teenage Mutant Ninja Turtles]

Sneak {1}{W} (You may cast this spell for {1}{W} if you also return an unblocked attacker you control to hand during the declare blockers step.)
Return one or two target creature cards each with mana value 3 or less from your graveyard to the battlefield. We Turtles don’t know the meaning of the word defeat.