Someone in the l337 world who knows what's up. This person can get you what you want, tell you what you need to know, and take you where you want to be - all with the click of a mouse or the tap of a keyboard.

Also someone who means business and is always serious.
Yo, check with Billy, he's h4rdc0r3 and can hook you up.

or

Man, don't fuck with Johnny, he's h4rdc0r3.
by ack October 5, 2004
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