la sombra negra
A group of Salvadoran thugs who make sure MS-13 doesn't get too big for their boots.
'La sombra negra came to my house and told my mom I was going to jail if I didn't stop stealing.'
'They said la sombra negra would beat me up if I didn't pay them back.'
'La sombra negra showed up at the party and told everyone to shut up or else they'd get beaten.'