If you make a controversial statement, it is best you have the evidence to support it.
Mark: I'm thinking of telling Evgeny that Communism is overrated *shocked faces*
Adam: Mate, if you throw a shit into the room, you better be able to lock the door!
"I'm gonna throw my shit around" in this context means to throw one's weight or power around, it is typically said right before doing some kind of impressive move or big attack.
"hold on lemme charge up an attack... I'M GONNATHROW MY SHIT AROUND!!"