In the original German release the 20th mission had to be unlocked by achieving a high enough rank during the course of the previous missions, however in all other countries the 20th mission is accessible to anyone who can reach it regardless of rank.
Date: Feb 11, 1945 Place: Gundelfingen, North of Freiburg.
Historic Background: The Soviet Army has entered East Prussia. The end of the Third Reich seems to be imminent. Suddenly, a secret teletype casts a dark shadow over the confident Allied command: detailed technical plans of Fat Man, the first nuclear bomb developed in the Manhattan Project, have been stolen by a Nazi spy and lead across the Atlantic to the Gundelfingen castle, north of Freiburg. From there they will be taken to an underground secret base somewhere in the Carpathians, where a German atom bomb is in the final stages of development.
Objectives: Your objective will be to enter the castle and put an end to this terrible threat.
Tactical advice: Officer. This is your most important mission ever. Unfortunately, I can't give you any details. I'm afraid you'll be on your own out there. The only thing I can say is gain access to the fortress and raze it to the ground. If you succeed, this could mean the end of the war. If you fail. May God protect us. Our eyes are set on you and your men. Good-bye and good luck.. son.
MISSION 20 WalkthroughEdit
TINY'S STARTING AREA Start by climbing wall and killing patrolman. Kill guard on corner, then up ladder, up again to kill turret guard. Back down and down drainpipe, kill all 3 quick and hide bodies. Stand/crawl knife/hide guard northeast of you. Place decoy against wall in front where it bends towards the steps. Crawl to edge of roof and stand, attract up to 6 guards (in 3 lots) Crawl to corner where downpipe is, stand and get em as they mount the steps As they gather use the decoy to make em stand still as you knife/hide em. PARAPET Crawl around the outside knifing as you go except the S most guard too hard to time. Finish with the crawl run/knifing of the 2 near the steps. Down ladder left right of building you passed. TARGET RANGE Operate switch and run to corner of wall & building, get caught. Marine enters via water, harpoon the 3 guards, bodies hid where Tiny was. Tiny goes past gap leaving decoy near well, decoy patrolling guard. Decoy placed behind fence near top shooting guard, knife/hide as he checks target. Decoy again to distract the awkward guard, knife/hide south middle guard. Move Decoy north to draw in guard behind gun. Decoy down to SW most target wall. Tiny behind next up. Knife (eyeball guard over road) run north, using targets for cover, dump body. Stand/crawl in front of corner targets to draw in eyeballed guard. Stand next to building edge and fire guns to draw in guard from top level, shot him. Knife/hide guard at edge of target range (if still there) SOUTH GATE Run/knife the right then left, hide right first behind corner sandbags. Run/knife right outer guard hide behind rock, repeat for left guard. Guide spy through patrols, crawl others to rock right of entrance. Everyone to sandbag corner. SOUTH WEST HOUSES Tiny cross gate to house nook, drops decoy, crosses gap Knife/hide south west most guard, hide behind house. Start decoy (eyeball top right stationary), knife two who come. Decoy behind south most house knife guard Decoy behind the left most guard, knife/hide the right one, turn off decoy Knife/hide the right guard. NORTH WEST COMPOUND Remove the last corner guard from the target area if still there Move Spy and Tiny over to the south west houses and into the middle of the NW. Tiny runs behind NW house so guard spots him at the outhouse. Spy injects the guard and times a run to the clothing. Distracts guard near balcony walls. Tiny knife hides the 2 guards south of them, the near gate and 2 gate guards. Spy injects the distracted guard too. Tiny & Spy clear the outer guards. DO NOT hide in nook of West most house, will get seen when patrol jinks. Drop bodies against the NW face of the house. NORTH PARAPET Spy drugs NW guard then one at top of steps, one at bottom of steps. lastly the one facing the courtyard. Run to the roof of the HQ NW. Clear the 2 on the main roof, 1 facing east on the lower roof. Guard on the corner and then run drug the patrolman. Drug the 2 outside the HQ (barge the right one for extra time). Back to the NE parapet, distract the front left guard Tiny knife/hides the right and patrolman. Spy drugs the left and north facing guard. Down a level and spy drugs the corner guard (eyeball the ground corner guard) NE courtyard. Drug all three, use tiny to get all bodies up a level (eyeball patrol) Driver & Marine up one level next to tank, Sniper & Sapper one level above. Spy distracts right guard as Tiny knife/duck guard looking down steps (tough timing) Knife/ducks distracted guard. Knifes roof guard (eyeball lower stairs guard, other is distracted) Spy distracts left most guard, Sniper shoots 2 guards and gunner from NE parapet. Tiny knifes last guard. Sapper places explosives between the HQ and the anti aircraft-gun at the NW part of the roof. Everyone gets to the Tank. Sapper blows the charge. and gets in. Final reward, use the tank to destroy all the buildings, the V2's and troops. Exit SW.
- This is the only mission in Commandos: Behind Enemy Lines that you can control all the commandos since it is a final mission of the game.
- This is the only mission where alternative history has occurred. While the project itself happened in real life, Gundelfingen, where the mission takes place, has no relation to the German Nuclear Project.