Stormcaller

Stormcaller is the great horn that can conjure up rain and water upon the lands. There is a legend that when it is blown, it will save the kingdom of Ascalon.

The mouthpiece of the horn is discovered by Prince Rurik at the end of the Ruins of Surmia mission. During the Nolani Academy mission, Prince Rurik uses the mouthpiece in conjunction with the rest of the horn carved in the cliffside to summon a soft rain and weaken the Charr forces besieging Rin by putting out their fires as seen in the cutscene.