The sub_base_b4.zip file you have requested: Maps Levels Missions / Objective / S Titles / Sub Base (Beta 4) - 21.81mb is not available. Perhaps try browsing all files for the game Wolfenstein: Enemy Territory and upload any files you want to share or are missing. This is the only information we could locate:
For more information on Return to Castle Wolfenstein: Enemy Territory, visit Returntocastlewolfenstein.filefront.com The allies have taken control of an Axis Sub Pen, The axis are mounting a counter attack using an elite squad to steal back the decoder. The allies much prevent this at all cost, the axis must get this decoder or lose the advantage in the war.