My original intention was to go through the levels of Sonic 3 & Knuckles, so after this will come Mushroom Hill Zone. I will progress through those, and as for running out of zones? Well, truth be told, I haven't thought that far ahead. Never in my wildest dreams did I think I'd still be doing this after five years, and it'll probably take me that long to get through the other zones. By that time, I may be forced to end the comic for several reasons.