It has been sixteen years since the Starks, Baratheons, Tullys and Arryns rose up in rebellion against the Targaryen rule. The last two living Targaryen heirs have fled to Essos, where they muster an army and wait for their time to return.
Meanwhile, the threat of White Walkers has become worse. With the birth of dragons coming ever nearer, the White Walkers are also making a reappearance.
The Maesters of Oldtown spent months trying to find a way to stop the White Walkers. Finding old documentation, they made the discovery that only Obsidian, or Dragonglass, would be able to destroy them. The houses of Westeros then each went in search of ancient weapons, that had belonged to their houses for centuries, and had mysteriously vanished.
The houses had been thrown across the world, to try and find these ancient, lost artifacts, in order to defend the realm from the destruction that would be brought upon them by the threat from the North.
The Starks went in search of the Shield of Winter, a huge shield with a sharpened edge made of Dragonglass, and coated in the same material. The Baratheons had the Storm Claymore, a huge two handed greatsword with an obsidian blade. The Tullys had their Dragonglass war scythe. The Arryns their glaive. The Tyrells their Halberd. The Martells their spear. The Lannisters their long lost house sword. The Greyjoys had their dirk.
The houses were determined to find these weapons, however, they also went in search of the weapon of House Targaryen: their Dragonglass flamberge. However, word has reached Viserys Targaryen in Pentos that the houses search for their weapons, and is determined to find them himself, to make the Westerosi pay for their betrayal of his house, to make them welcome him and his sister back with open arms...