Where winter was the focus of Endless Legend’s last add-on, developer Amplitude has revealed the seven seas will play host to its next. Tempest marks the 4x fantasy strategy’s fourth expansion, bringing with it naval battles, new mechanics and the Morgawr—an aquatic-based Major Faction specialising in naval warfare and the “manipulation of other creatures.”

What that means exactly remains to be seen, however we do know that factions will be able to “fight for dominance of the oceans through the control of sea fortresses,” so says a post on the Amplitude blog. “Although they will have to wrestle these from the grasp of the Fomorians, a new Minor Faction.”

A new weather system is tied to seismic activity beneath the waves, where Endless relics “provide strategic and luxury resources as well as other bonuses to the empire able to control them.” This can only be done by besting their assigned guardians, but, in a bid to thwart your occupation, will ravage the surrounding area with some pretty brutal weather conditions. You've been warned.

The update post continues: “New generated ocean regions, including a Sea Fortress, offer strategic locations in the water for players to battle it out. Anywhere from zero to three fortresses are located in each ocean region, so expect more in oceans that are more strategically pivotal, between islands or continents.”

No release date or price for now (previous paid updates have cost between £6.99/$9.99—£9.99/$12.99), however you can sign up for the closed beta by heading this way. Places are however limited.