Oathbow

Bow whispers "Swift death to my enemies" in
Elvish when you nock an arrow. You can reply,
"Swift death to you who have wronged me," to
make the target your sworn enemy (until it dies
or 7 days later, then you can choose a new
enemy). Against that target, you have advantage
on attack rolls, ignore partial cover, and attack at
long range with no penalty, and do 3d6 extra
damage.