Since this was an anniversary, there had to be a cake. In fact, not just any cake, but a big-ass cake. And, of course, such a big-ass cake would have to have big-ass candles. Which, I figured, would set off some sort of repressed memories in Mega Man's mind involving the various fire-based Robot Masters he's had to deal with over the years. And that, of course, would lead him to want to destroy the source of the anxiety, namely the cake. Which would then lead to the classic Looney Tunes "covered in soot" shot, complete with the still-white eyes and the sooty cough. I know, comedy genius, right?
On the graphical side, the cake was created by manipulating candle sprites from Shade Man's level in Megaman 7, and the thought-bubble cloud was created by manipulating the clouds from Cloud Man's sprites.