If you know 2fort4-5 then you know how to play this map.
A couple of new things added:
1) The enemy flag located in the basement has two entrances to the flag
room; the main corridor and the Vent located just outside the door (Shoot to
2) The Spawn rooms have a Push effect to keep the spawn camping down. If you try
and enter the enemy spawn room you will be pushed back out.
3) Under the bridge is the water access to the fort. The water entrance door has
to be shot before it will open.