Elevator Action/Walkthrough

Know Thy Enemy
If the building were not occupied by enemy agents, there would virtually be no challenge to Elevator Action, because enemy agents are the only threat to Otto's existence. So it is important to understand all of the way that you can remove them from your path, and keep yourself safe.
 * Shoot them: The obvious method. Use your gun to fire at the enemy agents.  Remember that they can crouch under your standing bullets just as you can crouch under theirs.  However, they can't jump over yours the way you can jump over theirs.  Therefore, they can never avoid a crouching shot from you.  The most convenient time to shoot at enemies is as you are coming down in an elevator.  However, this is also when you are most vulnerable.  Additionally, you can't crouch inside of an elevator.  So judge the situation carefully.  If an enemy looks like he is ready to shoot at you as you arrive, prepare to...
 * Drop kick them: In the event that an enemy looks as though they might have the chance to fire at you before you can fire at them, and there's no way for you to avoid it, the next best course of action is to jump and drop kick them.  One of the best times to attempt this is as you are coming down in an elevator, and they are standing right next to the elevator shaft.  Begin your jump just before the elevator gets even with the floor, and push towards the enemy.  By the time the elevator levels out, you will be on your way down, and your feet will hit the enemy's head and knock him out.
 * Drop a lamp on them: One tactic that you can employ to increase your safety is to knock the lights out in the building. It makes it harder for the enemies to find, see, and react to you.  Another benefit of shooting a lamp is that it might fall on an enemy's head and knock them out.  Take shots at lamps just as your gun clears a floor.
 * Sqaush them: It's extremely difficult to do on purpose, but it is possible to squash enemy agents with the elevator. Of course, they have to be standing under an elevator as the elevator approaches its lowest available floor, and that's not a common occurrence.  One thing to be aware of is that while the elevator squashes an agent, your descent will slow down momentarily, which may make you vulnerable to another agent's attack if you're not careful.
 * Let them fall: It's also a very unusual occurrence, but enemy agents occasionally fall down elevator shafts, especially when they are standing on the small platforms between parallel elevators. There isn't much that you can do to ultimately affect the chances of this happening.  Just wait a while in the lower floors of the building, and you're likely to observe it happening.

Doors to Destiny
When you encounter a red door, it's important to time your entrance and exit safely. Obviously, you'll want to clear the way before you enter a red door. Do not enter a red door while there are still enemies on the floor. They'll only be harder to deal with as you leave. Once the coast is clear, enter the red door. You can stay inside the red door for up to five seconds. After that, if you have not left the room, you will automatically exit. Use those five seconds to determine the best time to leave. Preferably, you'll want to leave after an enemy agent has just walked past the door and is still facing away from the direction that you will be appearing from. If the enemy is facing you when you exit, or there is more than one enemy present on the floor, make sure that you crouch as soon as you are all the through the door, and fire immediately.

Leap of Faith
The elevator is not the only way to cross an elevator shaft. As long as an elevator is completely above you, you can leap across the shaft with relative safety. If the elevator is on its way down, time your jump carefully. You can not jump across the shaft if the elevator cable is in the way. You can walk on top of the elevator, but you can not physically cross that cable. Bullets (your's or the enemy's), however, can cross the cable. Make sure that you only jump across a shaft when you are standing on one edge of the shaft. If you fall down the shaft even one floor, you will lose a life. You can drop down into an elevator as it's on its way down to the next floor.