While some New World bosses, such as Boatswain Ambrose and Alastor the Vigilant, credit you with victory just for landing a hit, the Zane fight is a bit different. Until the problem gets patched, you’ll want to exploit his weaknesses as much as possible to clear this quest.
New World Overseer Zane - Overseer Zane location
Overseer Zane calls Ebonrock Cavern his home in the northwestern parts of Everfall. It’s fairly easy to find just by following the quest marker, but you might find he’s not there once you arrive. Like New World’s other bosses, Overseer Zane disappears after being defeated and only respawns after a set period of time elapses. You’ll need at least one anti-Corruption potion before starting the fight. The quest prior to the Overseer Zane quest teaches you how to make them, but if you used it already, craft more before venturing in. The cave’s Corruption wears down your resistance over time, and you certainly don’t need another hurdle to defeating Overseer Zane.
New World Overseer Zane - Overseer Zane spawn rate
Unlike Ambrose and Alastor, just tagging Zane no longer counts toward the quest requirement. You have to inflict damage beyond a certain threshold - one we, admittedly, haven’t figured out yet - before it counts as “defeating” Zane. He’s weak against Thrust damage, Arcane, and Nature, so equipping weapons and items with any of those attributes is the best way to try and get over that threshold. Some of New World’s best weapons, armor, and builds should help give your party a competitive edge in the fight. You’ll likely be running out of inventory room at this rate, so it might be a good idea to pause and craft some bags before carrying on further.