SWORDBASE
Like all the multiplayer areas in Halo: Reach, Swordbase was developed as a multiplayer map first and handed over to the single-player team to incorporate into the campaign. That's a big change for Halo, and Bungie hopes it will make the competitive portion of the game feel more closely tied to the story elements. Also, it looks cool that way. You'll see Swordbase -- an abandoned Office of Naval Intelligence building ... in the campaign, but Bungie hasn't said exactly when or where it will show up. Regardless, it's a fun one. Super vertical and really tight, it's packed full of gravity lifts and death opportunities. The jetpack is ideal for navigation here -- you can jet up to the highest floors with ease, or break your fall after a huge jump to the ground.
Swordbase can be confusing at first: a maze of bridges, hallways and lifts. A good way to keep things straight is to recognize that there are two halves to the level, A and B, and all the floors and areas are labeled accordingly.
In the center of the map is the Atrium. The ground floor here sees lots of action, but it's still easy to miss the Sniper rifle at one end. It's on the ground between two planters -- just under the Low Bridge. High above the Low Bridge is a sneaky sniper spot which you can jetpack up to with your Sniper Rifle. It's a hole in the upper part of side B.
Three bridges span the Atrium area. At one end of the Low Bridge is a Health Station. The Middle Bridge has the awesome Plasma Launcher just waiting to be grabbed by a lucky jetpacker.
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Of the two sides of this map, side A really has all the goodies. The Beam Sword can be found in the Lobby area of 2a, propped against the wall under some TV monitors. Across the room is a window leading to the Atrium. A Health Station can be found here.
On 4a a staircase leads up from the Meeting Room (with unique tiles). Under the stairs you'll find the Shotgun. Nearby are a few Plasma Grenades on the ground, so keep an eye out.
Side B has a Health Station in the Control Center on 1b, just at the bottom of the stairs leading up to 3b.