Atrill is the Second-in-Command Red Koopa Troopa, a member of the Dark Schneiders. Apparently, he was formerly a member of the Koopa Troop, until expulsed by King Bowser of the Koopas. He later took up residence in Biene City, and was invited to join the Dark Schneiders by Denthrahir. Quickly accepting, he rose through the ranks of the gang until he was Second-in-Command.