Random(?) the question mark is a secret boss in IWBTB.
To get to this boss, you have to walk in endless screens where you get Scouter. However, since version 1.3.3 he is unaccessible.
He spins around in circles and shoots glowing orbs. This attacks is simular to Sonic's emerald attack and Ryu Hayabusa's last attack.
He stays at the top and shoots homing glowing orbs. After about 2 seconds he spins around in circles.
He hides below the platform and shoots lots of raining greens 0s and 1s.
He dashes from right to left.