Xin'vala's Wrath

This +1 glaive deals an additional 1d8 poison
damage. When attuned and worn/wielded by a
dragonborn, that dragonborn can breathe
underwater, gains a 30 ft. swim speed, and does
not have disadvantage when attacking with the
glaive underwater. In addition, the breath
weapon range is increased to 15-30 ft. (decided
each time you use the ability), and the damage is
increased by 1d6.