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?"
SHUT IT DOOOWN.
Real talk, Ortega's got a huge scrap vs. ex-champ Frankie Edgar -- a fighter he considers "a legend" -- at UFC 222 this Saturday.
Guessing he'll be a tougher test than Van's grammy ... just by a little.