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This mission is much like the others with the same background and is straightforward. Keep moving left and up, watching for flamethrowers and grenadiers. However, there's some good news. Unlike the previous Emergency Missions, this one has absolutely no time limit, so you can get through at your own pace.

For enemies right at the edge of areas above you, you will NOT be able to shoot them horizontally from the ladder. However, you can hit them if you aim diagonally at them.

When you are running along a corrdior and see flames above you (at the top of the screen, not from the ceiling), this is a sign that you are about to encounter a tricky flamthrower. To get past him, stay on the right ladder until he begins to approach, then quickly leap to the other ladder. If done right, he will be at the endge of the platform and will be far away enough so that he will not fire. Then dispatch him with your weapon of choice.

In the room after, you will come to a point where the left and up rule will not apply. There will be two ladders on each side in a shaft above, and if you move right in the corridor below you will hit a dead end with a medkit at it. Go up the right ladder to confirm the position of a flamethrower above; don't worry, if you're careful and move slow he won't hit you. Then move onto the left ladder and get onto the pipe. Move back towards the flamethrower slowly. When his face is on the right side of the screen, change to the shotgun and take him out. If you need health, back on the left side you can move left a little ways to find another medkit. Then continue right and go up the ladders to reach another pipe.

If you move slow, you will spot another flamethrower. In order to conserve ammunition, look for the shadow of the floor and move a short ways in before dropping down with Down + B; if you drop too soon, you will only graze the edge and fall very painfully if you do not grab one of the other ladders in time. If you do though, hold right and up as you fall; you WILL grab the bottom ladder and save yourself a world of hurt. A good gauge of how far in to drop is the damaged section of the wall in the background. Move near it so the flamthrower will shoot but will not hit you. When he pauses, drop down and duck, then proceed to destroy him with the rifle (or machine gun if you prefer, but it is good to conserve ammo). Continue left again to move into the next room.

Inside, move right until you get to a pipe on the ceiling with a ladder on the wall. Go down the ladder and grab the medkit (if needed) and ammo at the bottom, watching out for the flamethrower guarding them. Proceed along the pipe as normal, using the shotgun + pipe tactic on another flamethrower on the other side. Up and left applies again here until you reach another dead end with a medkit. Take it, then go across the pipe near it and go right. If up until this point you've taken all of the ammo for the machine gun, take the one near the door for the shotgun, as you will undoubtedly be running low and will need more.

In the next room, you'll be at a ramp where a flamethrower will be in front of a grenadier. Equip the shotgun, then run in firing range of the flamethrower (yours, preferably not his) and take him out as quickly as you can (2 shots on Easy). Use the shotgun and you will do just fine, or, if you can stand taking a little damage, you can use the rifle or machine gun. Then proceed to take out the unprotected grenadier. Eventually you will reach a really long shaft downward. Climb down the left ladder and go all the way to the bottom; the passage on the right side leads to an area you will end up in anyway if you go to the bottom. Move right and take out the enemies and you will see why it was a good idea to go to the bottom when you reach the ladder, for in front of it will be a medkit you probably need. Climb up the ladder and proceed up and left as normal.

Eventually, you will end up in a room with a sliding door. This indicates the boss is nearby. Take out the flamethrowers in this area and equip the shotgun. Move right and start shooting at the large flamethrower guy; he is the boss for the level. Pop off one or two shots at him and run left, repeating until you are behind the sliding door. He will turn away and stop shooting once he hits where the door is; give chase and take him down by shooting him in the back. When he is dead, the mission is complete.