The Diablos are a Puerto Rican gang appearing in Grand Theft Auto 1, Grand Theft Auto III, Grand Theft Auto Advance and Grand Theft Auto: Liberty City Stories. Diablo is spanish for Devil. They are a fairly small gang, and not very well armed. The leader of the Diablos is El Burro (who has been under observation by police since 1997, as mentioned in GTA III's official website). The only activities known to be associated with the Diablos are street violence and pornography, although they had also been known to engage in gun battles with the Liberty City Triads. They also appear to be having spats with the Uptown Yardies for dissing Queen Lizzy, and with the Yakuza for trying to steal some protection money, both times ending up in the slaughter of a large number of Diablo gang members.
The Diablos play an important role in GTA Liberty City Stories being one of the gangs used by the Sicilian Mafia to attack interests of the Leone Family. They are first seen when Toni Cipriani is enlisted to follow Massimo Torini, then a member of the Leone family after Salvatore Leone suspected somebody was betraying him. Massimo meets with a group of Diablos at Hepburn Heights and tells them that if they worked with his associates (later revealed to be the Sicilian Mafia) Hepburn Heights would belong to them. The Diablos then attacked the Leone Family goons in a large scale battle that takes place in Hepburn Heights, where the Leones are overwhelmed by a large quantity of Diablos armed with MAC-10 sub machine guns. The fight was won by the Leone Family, but Toni says that the Leone wouldn't be able to hold on to Hepburn Heights much longer. This would be true, as the Diablos have control of Hepburn Heights in 2001, the setting of GTA III.
Diablo members are seen wearing dark blue jackets donning the Diablo's gang logo (a yellow crown) on the back, long pants and bandanas. In GTA Liberty City Stories, Diablos members don fishnets or red skullcaps on their heads, red shirts, and black or brown pants. They drive Diablo Stallions. The gang is mostly based off the Latin Kings, as Both Diablos and The Latin Kings have the yellow crown as their logo. Coincidentally, the Spanish Lords from Grand Theft Auto IV and the Diablos both have the same construction (both Puerto Rican gangs, yellow crowns as logo, etc).