DC Universe Online's new summer event, Tides of War.
Tides of War is set against the backdrop of Aquaman fighting Ocean Master for the crown of the seas. Their respective followers have amassed fleets around DCUO's cities, and players can assist the side of their choice via with new missions, feats, collections, and a four-person alert. There are plenty of rewards to entice super-loyalty during this event, including pets and costumes.
The event will go live with Game Update 16.