A state of epicness entered when you are in need of enhanced power, skill, or all out brutality. Similar to Super Saiyan.
Eg: In the 2010 NHL playoffs, Ryan Kesler went into Beast Mode, playing with a f*cked up shoulder and still making the other teams his b*tch.
"Did you see McGregor knock that guy out last night?"
"Yeah man, he was in Beast Mode!"
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