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Security Door

This switch consists on a double layer door, each half opened with a separate 'key'. The first part of the door is opened by inserting the first key (a plasma grenade) and the second is opened by inserting the second key (a power drain). These two keys can be placed in different places around the map to make it more or less difficult to obtain them and open the door, but for this example map they are both provided on the wall between the key slots. Here are the pictures:

OVERVIEW:

The two keys (power drain and plasma grenade) on the wall:

Inserting 'Key 1' where it is carried to the back and destroys the first gravity lift. This causes another to spawn on the other side of the wall, next to the first layer of the door, and lifts the dumpster:

Inserting 'Key 2' where it lands next to two fusion coils and destroys the second gravity lift. This causes another to spawn on the other side of the wall, next to the second layer of the door, and lifts the dumpster:

First layer of the door opening:

Second layer of the door opening:

The door closed from the other side:

The door opened from the other side: