The North had fallen, and the wights spread throughout the Riverlands, and even a small host through the Vale. The wights from the ship were finally sighted, after a few empty fishing villages on the coast. The mountains served as great cover for the wights as they pillaged the hill clans and some coastal provinces, gaining a huge army. Walder Frey and most of his children were slain when the wights crushed the Crossing from both sides. Seagard was next, where the white walkers were as ruthless as before. Then, they circled Riverrun.
Without being able to cross the rivers, the king was trapped on three fronts. Edmure Tully and his young son were trapped on all three sides of the triangular castle, bombarding the fifty-thousand-strong host of the dead.
The white walkers in the Vale had a tough time with Heart's Home. Lyn Corbray slayed one of the white walkers, not a wight, with his Valyrian steel sword Lady Forlorn. But they finally won, executing the Corbrays, and then came upon the Eyrie. Now, this one was even harder. A mountain fortress, the wights had to pass three gates to even get to the castle itself. Little Robin would be safe for a while, at least until the knights of the Vale showed up.
By this time, Stannis had concluded his battle against the Lannisters. Tommen and Myrcella were put to the sword, and the rightful king was seated on the Iron Throne. The armies of the Great Houses that remained finally were able to revert their armies into declaring a joint War for the Dawn with the Iron Islands.
Riverrun fell, and with it the two Tullys, effectively extinguishing the line. Iron King Theon Greyjoy had joked that the Iron Islands would be safe unless the White Walkers learned to swim, but they didn't know about Riverrun and Seagard's vast navies. The king crammed all of his wights onto the ships and sailed for Pyke.
Robin Arryn was on his way down the little pulley system to escape when the wights crashed into the gates of the Eyrie. The knights who were helping him down were killed, and the pulley system was let loose. It was a long fall for little Sweetrobin, who perished very young. With the Riverlands and Vale crashing down with the North, only four kingdoms remained. But not for long.