Going to an asylum or mental institution? If this is fiction, then there’s a 100% chance that it’s going to be filled with raging, murderous psychopaths. There is 0% chance that someone won’t try to kill you.
Why this is bad: The idea that “crazy” (see: mentally ill) people are violent and dangerous is a myth that has persevered through history. Those who see themselves as normal see the crazy people as demented, violent, and best to be ignored. A long time ago, asylums existed to fulfill that exact wish and placed those who were mentally ill or deemed unfit for society in awful conditions where they were experimented on, neglected, and abused. Our media still reflects this idea, especially in the horror genre. This is despite the fact that people with mental illnesses are, on average, significantly less violent than people without. Nevertheless, 60% of people with mental illnesses shown on television are portrayed as committing violent crimes. When you write in the crazy patient who kills everyone, you’re helping create the stigma that causes society to actively discriminate against the mentally ill.
How you can fix it: I will be the first to admit that Outlast is one of my favorite games. It’s terrifically terrifying, and I love the story. Part of the reason I like it is because even though the people who attack you are crazy, it’s not really because that’s how they used to be: they were crafted that way. The corporation that bought the mental institute is shown to have taken completely sane individuals and those with mild disorders and experimented on them, purposefully making them hyper-aggressive and encouraging violent behaviors as they tried to create products to sell to the military. The people who attack you in the game did not start off violent; they were taken advantage of because of the stigma placed upon them and they were made to be violent. The main antagonists of the game were either those heavily experimented on or those in charge of the research and corporation.
While this still isn’t great for the stigma of “dangerous crazy people,” it puts a spin on it that lifts the blame from the ill and puts it on the abusive corporation and the normal people. If you desperately, absolutely need to have an asylum in your story – or anything else where the crazies live – then you should honestly consider not making the violence in the story come from the ill. Channel that somewhere else, and stop being so lazy as to say to blame it on a sick person.
Bottom Line: Don’t do it. But if you do, don’t blame is on the “crazy.”