A Centurion is a recurring ally in the Kid Icarus series. Centurions are warriors fighting under Palutena in the Icarus Army, Palutena's personal bodyguard, and is in charge of securing the peace in Angel Land. Pit is the leader of the Icarus Army.
During Medusa's invasion prior to the original Kid Icarus, the Centurions fought hard to defend Angel Land. The surprise attack from Medusa's troops caught them off guard however, and the Icarus Army was unable to fend off the attackers. Medusa was successful in taking control of Angel Land and the majority of the Centurions were turned into stone statues by Medusa's powers. The statues were placed in the fortresses in Angel Land, as decoration as well as barriers to stop intruders form advancing. The Centurions inside were still alive however, and by tapping them with a Mallet Pit was able to break the spell and release them. Any freed Centurions would then help him in the battle with the Gatekeeper at the end of the fortress.
In battle the Centurions are very weak, a single hit would be enough to defeat them. They attack using their bow, and in large numbers they pose a threat to any opponent, despite their weakness.
Kid Icarus: Of Myths and Monsters
The Centurion statues returned in the sequel, but this time they also appear outside of fortresses. Tapping them with the mallet doesn't release any Centurions this time around however, instead they may leave behind an item. It's unknown if this is because they are actual statues or if the Centurions inside them have died, but because of the larger quantities in this game, the former is more likely.
Super Smash Bros. Brawl
The Centurions appear in Super Smash Bros. Brawl along with Pit and Palutena. When Pit uses his Final Smash Palutena summons a large number of Centurions to attack his opponents. Just like in Kid Icarus a single hit is enough to kill them, but for unknown reasons they ram their opponents instead of using their bows in this game.
Centurions return in the long awaited sequel, resembling their prior appearances in the series. The new Fighter characters introduced in the game's multiplayer mode were originally mistaken as the Centurions.