This level's pretty dang small, but still tends to take a while because of the key gimmick. Every access key is held by an enemy of the associated color, and they're all bomb laying drones that tend to run away from you. Depending on your luck, hunting it down can take anywhere from a few seconds to several minutes.
The main area of difficulty is the area surrounding the yellow key here. Several missile-armed platform bots roam around, and the hallways don't offer much room to evade if you get ambushed.
Also, I hold off on grabbing the hostages until AFTER I blow up the reactor because leaving the hostage room triggers a spawn cycle on the points in the reactor room. Given that both spawns produce enemies with missiles and they're a substantial distance from each other, I find it too risky to try to farm out.
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