UFC rising star Brian Ortega lives by the warrior code -- anyone, anytime, anywhere -- and says those rules apply even if you're a 78-year-old woman!!
We got "T-City" and Bruce Buffer on the TMZ Sports TV show earlier this week ... and Buff told us Ortega's so game, he'd literally kick anyone's ass at a moment's notice.
Our guy, Van, countered with the freakshow fight of a lifetime -- a matchup with his own grandma!!
Brian's response -- "How much money we getting paid?