Nighthawk

Nighthawk is a level 94 Fabled helmet. Its major ID, Hawkeye, concentrates all of Arrow Storm's power into 5 arrows, each dealing 80% damage. As it does not change the casting duration of arrows, Hawkeye Arrow Storm can theoretically be spammed four times as fast as normal Arrow Storm, increasing your damage per second by quite a bit.

Identification
This item is likely a reference to Destiny 2's Celestial Nighthawk Exotic Helmet. It has a special effect that turns your 3/6 shots of your Super into one shot, which is similar to what this item does in Wynn.