Stinky'd means, that you just got EpIcAlLy TrOlLeD by Mario. In Super Mario 64, Mario says "Hey stinky!" And since then, it has been a meme where you would say "Hey stinky!" to someone that is taking a shit.

When you get epically Hey Stinky'd by Mario. You will be forever cursed with the Hey Stinky if you get Hey Stinky'd.