Now you can own the employer behind the team of assassins known as the Marauders when you order this X-Men t-shirt for adults featuring Mister Sinister. Shop Your Favorite T-Shirts for all your Marvel merch today. Now you can own the employer behind the team of assassins known as the Marauders when you order this X-Men t-shirt for adults featuring Mister Sinister. Shop Your Favorite T-Shirts for all your Marvel merch today.