This is a promotional shirt for Sonic Rush Adventure on the DS. Like the Jolly Roger flag it's meant to resemble, the shirt is black. Instead of the traditional skull & crossbones, it uses a white version of the SonicTeam Sonic face logo, and some stylized bones. The effect is nice, very pirate-flag-like! It's too bad this shirt wasn't made in larger quantities. This was auctioned off by Sega to raise money for the Japan Earthquake victims in 2011.