most people threatening to DDoS (Denial of service attack) are lying.
However, if this was to happen, please contact your internet service provider.
Here are some things that are illegal for A Denial Of Service Attack:
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* Loss to one or more persons during any one-year period aggregating at least $5,000 in value.
* The modification or impairment, or potential modification or impairment, of the medical examination, diagnosis, treatment, or care of one or more individuals.
* Physical injury to any person.
* A threat to public health or safety.
* Damage affecting a government computer system
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If any of these above do occur, you have the full right to report him to law enforcement.
Hope that helped!