Something that reminds me of the old King Arthur movies is a sword sticking out of the ground.

1. Go to the level Outskirts.

2. After the sarge gets into the pelican, look the way the pelican is not facing.

3. You will see two pipes, one higher than the other one. Jump onto the higher one and jump onto the roof.

4. Keep jumping higher and higher until you can't anymore.

5. Jump over to to little roofs hanging out on the side closest to the fiery pit.

6. Jump and when in the air hold crouch and land on the big platform hanging over the middle of the street. Be careful not to fall in the hole in the middle of it.

7. Look around until you see the tan building closest to the map's edge. Jump into it and there will be an energy sword sticking out of the ground near a pile of blood and rubble.

You can also jump onto the roof and skip most of the level by going on them.

Keep your eyes out for more hidden easter-eggs! Good luck!