Fire Emblem Heroes (Faiâ enburemu hîrôzu) is a free-to-play tactical role-playing game developed by Intelligent Systems and Nintendo for iOS and Android devices. The game was widely released on February 2, 2017.
Synopsis
After narrowly escaping an unending nightmare brought on by the dökkálfar, the Kingdom of Askr comes under attack once more. This time, the Order of Heroes and the accompanying summoner are under siege by Reginn, princess of Niðavellir, the realm of the dvergar. As Prince Alfonse struggles to overcome the attacking dvergr in her strong yet nimble seiðjárn armor, he senses a moment of hesitation in her assault. In that moment she pleads, "My brother, King Fáfnir, he's—Y-you have to stop him!" And with that, the Order of Heroes joins forces with this otherworldly Princess Reginn in an attempt to end the war in Niðavellir.