This is why mario went alone

“So it was 你 who was a-messing with our heads!” Luigi scoffed. “It was a good thing I snapped out of your twisted dark magic and all your illusions!”
King Boo snickered. “Merely a trap to not only get 你 to quit, but also to get 你 to give up altogether.” Then he added with an evil smirk, “But there were no illusions involved—everything 你 saw before 你 were real. Your 老友记 are really suffering; you’ll really be up against all the forces that are beyond your wildest expectations....”
“And as I’ve said—I’m going to save them no matter what!”
“Still so...