A Sonic & Knuckles theme is refreshing here on blue.
With this shirt, both characters get equal billing, with both standing in front of hot green grid lines over a huge "X". Sonic and Knuckles' names have been written huge in the background, and are outlined to look like they are reliefs in the fabric. Again, the logo appears 3 times. This shirt is a nice change of pace, and isn't too busy or crazy.