—Desaix's battle quote in Chapter 3
Years before Gaiden began, Desaix was willingly killing the children of the royal family. General Mycen tried to stop him, but Desaix charged Mycen with the crime and had him banished. Fortunately, Mycen managed to take the newborn princess Anthiese with him before Desaix could have her killed. 16 years later, Desaix began his rebellion, conquering the Zofian castle and killing the king. In response to this, a resistance led by Clive was formed in order to oppose Desaix. Eventually, Alm took control of the resistance and reclaimed Zofia Castle. What seemed to be Desaix, however, turned out to be no more than an imposter (which is revealed if the player kills Desaix prior to Slayde). After killing Desaix's general, Slayde, their foothold in the Zofian capital was no more. Afterwards, his remaining forces retreated back to their fortress of operations in Northern Zofia. Later, he manages to capture the Zofian knight Mathilda and demanded that she would be executed with arrows. Alm's army arrives just in time to save her. But having foreseen their army's approach, Desaix had requested aid from Rigel in order to finally thwart the Zofia Rebellion. Despite the aid, however, Alm's forces attacked the fortress and Desaix was killed.
**Dropped upon Defeat
Attempting to fight him at Zofia Castle is less than recommended, due to both his superior third tier class, and his massive army. You may very well stand a chance at defeating him and taking his dragon shield if you have promoted one of your villagers, namely Kliff, into a mage. Even with a mage though, beating him is no easy task. As mentioned before, Desaix has a massive army. Dealing with them is hard enough, and another ordeal is not killing Slayde (as killing Slayde forces Desaix to leave). Pick off the enemy one by one. Have Silque mend any wounds. Ultimately kill Desaix with magic, archers, and Alm, Lukas, or Forsyth. Also, another good idea would be to exercise your party members in the Rebellion headquarters before coming to the castle. Recommending an average of at least level 8 across the board if you're going to attempt this.
Here, unlike the first battle, it's obligatory that you kill him. This time he has several Armor Knights and Archers from Rigel with him. There will also be a Sorcerer in the forest, casting Fortify (who you may want to pick off with Clair at the start of the fight, to prevent Desaix from healing) and an Cantor in the upper right corner summoning Revenants. Finally, Desaix is a Baron, making him pretty tough to beat. By now however, you should have Luthier, who proves to be a great asset in this battle. Simply have him use Excalibur on the Armor Knights, and finally on Desaix. Support him with Alm in the front, and keep Silque nearby just in case either of them is damaged. Also, a very important note: Be sure to pick off the Archers quickly, to prevent Matilda from being executed (as she cannot fight back). Once Desaix and the Armors/Archers are killed, the rest of the map should be very easy to complete.
—If the player killed Slayde in Chapter 1 on Zofia Castle
—Desaix in Chapter 1 on the opening in Zofia Gate
—Desaix in Chapter 3 on the opening in Desaix's Fortress
—Slayde, if the player defeated Desaix in Chapter 1 on Zofia Castle
In Other Media
Desaix appears in the Fire Emblem Gaiden manga. His design slightly differs from his in-game portrayal, where he has a beard. During the manga, he loses his eye in battle and kills Kliff, one of Alm's soldiers. As punishment, Alm's army has him impaled on a spike.
- The real Desaix has a unique battle purple palette, unlike the imposter fought earlier.
- He is the first character to be shown in battle as a Third Tier unit in the entire Fire Emblem series.
- Most of the bosses in Gaiden share a palette swap of his portrait.
- He had a mustache in Gaiden, but a beard in the manga adaptation. In Echoes, he has both.