Mana Warden's Bow

When you cast Mana Warden's Bow you may pay {u}{u}. If you do, create a 2/2 Blue Construct creature token. When Mana Warden's Bow enter's the battlefield, equip it to that creature.
Equip {2}.
Equipped creature gets +1/+1 and "{t}: Deal 1 damage to target creature. Each player puts the top three cards of their library into their graveyard."