The two singers engaged in an all-out prank war during their Indianapolis show on the Believe tour earlier this week and definitely got each other good!
First Justin started it off when he popped up during Mike's opening set and came out with a mannequin! We aren't really sure what's up with his mannequin obsession these days...
Mike got Justin back during his performance when he went out on stage dressed just like him!
Check it all out in the video above!
Which prank did you like best? What's the most epic prank you've ever pulled?!
Watch more of Justin's epic pranks on his celebrity friends HERE!