It works best with a friend online or with a second controller in Deathmatch. The map does not matter. Pick up the Shuriken box where the single shuriken can be thrown ( The box has a Bigger Shuriken pictured) not the others singles 3 where fall on the ground. So if you have the Shuriken go all the way up to the left where you can change the page and look to the left side. The other player now goes up right to the other side. Now throw the Shuriken with
to the left and he will kill the other player to the right.