Harbinger
From Dungeon Defenders 2 Wiki
Harbinger is the boss on the Harbinger's Warship mission. He has 4 phases. His attack patterns vary from each phase.
Overall map objectives
Defend the Ship's Engine from attacking monsters while defeating the Harbinger. Monsters will continuously spawn until the Harbinger is damaged enough to advance to the next phase. Players will be given a limited time of 90 seconds in-between each phase (except the beginning where players have an unlimited time to build as usual)
Phase 1
Harbinger will use the Harbinger Cannon on-board his ship to deal damage to the ship's engine. Harbinger Cannons can be destroyed.