Amazon would like you to know that there are some very strict rules about how you can use its new video game software ... unless there are zombies around.

The company recently released Lumberyard, a free-to-use platform for video game development that's linked to the Amazon Web Services cloud platform.

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Amazon updated the terms of service for AWS accordingly, adding a section that says the Lumberyard platform can not be used for life-saving or safety-critical equipment like spacecraft or military arms.

But ... there's a zombie clause too.

"However, this restriction will not apply in the event of the occurrence (certified by the United States Centers for Disease Control or successor body) of a widespread viral infection transmitted via bites or contact with bodily fluids that causes human corpses to reanimate and seek to consume living human flesh, blood, brain or nerve tissue and is likely to result in the fall of organized civilization," section 57.10 of the terms document says.

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Representatives from Amazon were not immediately available to comment on Lumberyard's potential uses against the undead.

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