Nabarl

Nabarl (literally Nabaaru, translated Navarre in the American version, Nabaaru in Super Smash Bros. Brawl, and Navarl in the anime) is a stoic mercenary known as the Crimson Fencer and infamous for his Killing Edge, often working with bandits for unknown reasons.

In Fire Emblem: Ankoku Ryū to Hikari no Tsurugi, he was assigned to chase after Lena and Julian, but changes his mind and joins Marth's army when Shiida asks him to, in part due to his policy not to harm women or children he encounters. After the war he vanishes.

In Fire Emblem: Monshō no Nazo, he reappears and returns to banditry once more where he encounters the dancer Feena. After hearing that the Altean army approaches them, Nabarl once again defects and protects Feena along the way. He helps Marth out of respect from the last campaign, but once again vanishes once the campaign is over with Feena following him.

A little of his past was revealed in the OAV. A scene of him having a nightmare, where a woman is shown to be killed, can be seen in Episode 2.

Nabarl is a Sticker in Super Smash Bros. Brawl.

(Source: Fire Emblem Wikia)