Rifts on the Coast Trigger: Visit the Storm Coast for the first time Reward: +1 Power, +80 Influence per Rift closed, +2 Power and +200 Influence for closing both.
The Vinsomer will leave that area if the giant dies or the Inquisitor gets close enough to encounter the battle The biggest secret of Storm Coast requires the execution of a war map missions to access.
It looked like it had been initially created to be used but was scraped.