While playing through level 4 don't forget to take a moment to gaze at the stars in the large arena with the three Poopsy Generators. Be sure to kill all of the enemies in this room first so you can star gaze without getting killed. Now, using
Kurt Hectic's sniper scope, zoom in on certain special stars in the sky (they are usually slightly pinkish in color). There you will find the crack team that made MDK2 possible gazing back down at you, along with their Wu-Tang Clan names.