Outskirts Energy Sword
From Halopedia, the Halo wiki
The Outskirts Sword can be found on the Halo 2 level, Outskirts. It is also known as Excalibur. It is in the top level of a building not far from Hotel Zanzibar. The building's roof has a large chunk missing, suggesting something hit it. The sword is embedded in the floor, next to a arrangement of rocks that spell out Rex and blood stains. Oddly enough, the 'Rex' does not always appear, usually when playing co-op. While many claim it to be the only sword in the level, a Stealth Elite, SpecOps Elites, and an Ultra may draw their sword if they feel threatened.
WARNING!: Getting this Energy Sword will cause an Ultra Elite to attack Hotel Zanzibar (if you have not already killed the enemies there).
Directions
To reach the sword, one must get to the Rooftops Vacation. This can be accomplished at the very start of the level. As soon as you exit the room with the crashed Pelican, jump onto the door frame. From there, jump onto the higher platform. It should be noted that the Blind Skull is nearby. It might be wise to bring a Sniper Rifle in case Covenant bother you. Make your way over the rooftops to the sword.
