Metal Sonic makes a rare poster appearance. They didn't really do a whole lot with him, just taking the official Japan stock art and spamming the same one all over the poster, but in different sizes. The background is a rather clashy green with orange wiggles.
Of course, the stock art of Metal Sonic is great, with smooth chrome effects and very good shading. The most curious thing about the poster is the odd little symbol appearing at the bottom. (Close-up photo above) It's vaguely "Transformers-ish" but really looks like it may mean something...though what isn't known. This is another STC poster.