Gassantoda

The Battle of Gassantoda (月山富田城の戦い, Gassan Toda-jō no Tatakai) is a fierce battle between Amago and Mōri

Role in Games
In Mouri Motonari: Chikai no Sanshi, the first battle appears in chapter 7. After the Ōuchi army falls into the Amago army's trap, Motonari realizes there is no way for his forces to retreat. Kayō and Masahira volunteer to sacrifice themselves in order to open a path for Motonari.

After the Battle of Itsukushima, Amago Haruhisa suddenly dies, leaving Yoshihisa to succeed the clan and gather troop for declare war against the Mōri. Motonari sends his son is Motoharu and Takakage to fight against Amago. However, Yoshihisa is too hesitant to face off against the more experienced Mōri forces.

Later, Yoshihisa recruits Shikanosuke to fight the Mōri only to lose and be taken captive. Motonari shows mercy by sending him to live in exile as a monk.

In Samurai Warriors 4: Empires and Nobunaga's Ambition. The Gassantoda Castle was a main stronghold of Amago clan.

Historical Information
The Battle of Gassantoda occurred thrice. In the first battle, the Amago army set a trap around the castle to lure the Ōuchi army, causing many casualties. When Motonari, who allied himself with the Ōuchi, arrived in the battlefield, he found himself surrounded by the Amago. Motonari broke through the enemy ranks with aid from Watanabe Kayō who died as a result. After the battle, Ōuchi Yoshitaka turned his attention to the arts rather than the war effort which caused Sue Harukata to betray him.

During the second round, Yoshihisa was gathering troops to defend the castle. At the time, Motonari had sent his army to attack. Yoshihisa attempted to repel the advance but could not stop the Mōri army. Upon failing to escape and taken prisoner, he agreed to surrender power and live as a monk, even changing his name to Yurin (友林).

In the third and final instance, Shikanosuke fought to regain the castle from the Mōri only to be entrapped by Amano Takashige.