how to be invisible
If you take pictures of Houdini splicers you will receive a special plasmid it's called natural camouflage. There are a few limitations to this ability. You have to stand still. It takes a couple of seconds. You can't open fire on a splicer and stay invisible. If a splicer sees you you can't turn invisible. But think of it turrets, splicers, security cameras, and even big daddy wont be able to see you.
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