A Koopa Troopa's only armor. After it has been removed, it can be used as a projectile to pown someone.
*Cheerleader gets hit by a Koopa shell* Powned! Or however you say that!
You say this when you kick something that's big and has the possibility to pwn sum1's nads
Guy 1: Hey dudes, check this! KOOPA SHELL! *kicks a rubber ball*
*Rubber ball pwns someone's nads*
Guy 2: Oooh sthhhhh! Aaaagh! my nads
Guy 1: Now u know y i said "Koopa Shell"