The Fall of Fynn is the first major event in Final Fantasy II. The battle occurs when Emperor Mateus of Palamecia discovers a resistance force in Fynn and invades the city. The event is a pivotal battle in the game's history, as it triggers many of its events.
The Emperor discovered a resistance in the city of Fynn and attacked. This was the battle where Scott was fatally wounded and from which Gordon ran. Hilda fled from Fynn with Minwu and the King after he was fatally wounded in battle as well. The four main characters, Firion, Guy, Maria, and Leon, were all residents of Fynn and were wounded while attempting to fight during their flight, with Leon being captured by the Emperor's forces. This event sparks Firion's passion to join the Wild Rose Rebellion.
Firion and his two friends are found by Minwu and healed at Altair. They set off back to Fynn and meet Scott, who gives them his ring before he passes away. Upon showing the ring to Hilda, she accepts them as members of the Wild Rose Rebellion. Leon is captured by the Emperor's forces and eventually becomes the Emperor's Dark Knight.
The Empire suffered considerable losses at Fynn, even though their Mythril equipment gave them a significant material advantage over the more simple-equipped army of Fynn. The resistance at Fynn effectively halted further imperial expansion, and Altair and Gatrea remained free from the Emperor's control. To compensate for this, the Emperor ordered the construction of the Dreadnought, planning to destroy the remaining resistance from air rather than through boots on the ground.