Legate Lanius

Legate Lanius is the military leader of Caesar's Legion and the final boss of Fallout: New Vegas. He resides at a camp located just beyond Hoover Dam, where the final battle takes place, and cannot be reached until the end of the game. Lanius is the Legion's most savage and bloodthirsty warrior of all, and even Caesar himself says he's only in it for the killing. If Caesar dies, Lanius becomes the new "Caesar" and the Legion becomes even more brutal under his leadership than before. If the Courier decides to work with the Legion, the final mission is to defend the Legate's camp and kill the NCR general instead of the other way around, and Lanius appears to congratulate the player upon winning the battle.

He is by far the Legion's most physically powerful member, being a massively tall and muscular man sporting an intimidating golden suit of armor with a mask in the image of the god Mars and wielding an enormous sword known as the "Blade of the East". He is an outright boss character, with more HP than any other character in the game and several unique NPC perks that give him special abilities.

Lanius was originally the champion of one of the enemy tribes the Legion conquered. When his tribe's chief surrendered to the Legion, Lanius was infuriated because he never wants to back down from a fight, and turned on his own people, killing the chief and 15 others of his tribe before falling. His face was torn apart from his injuries, and when he woke up Caesar was there to offer Lanius a new life as his personal champion, with a special mask made especially for him. Lanius accepted, under the condition that he got to personally kill all the remaining males of his own tribe (Caesar only let him kill the adult males).

In one of Mr. New Vegas' radio broadcasts, he reports of Lanius disciplining an underperforming squad of legionaries by beating its commander to death in front of everyone, then having every tenth men in the group killed by the other nine tenths. When talking to Caesar, he confirms that this is a ritual regularly performed by the Legate.

It is actually possible to make Legate Lanius surrender without killing him with a perfect Speech skill of 100%, by convincing him that the NCR have set a trap for him and the fight is already lost, or that the vast NCR territory of the Mojave Wasteland would be too much for the Legion to maintain in its current state.