Cisco is first introduced to Mike in the mission Fine Dining, when King Courtney attempts to get Mike to kill Cisco. Cisco, after getting beaten up, manages to convince Mike to work for him. After getting Cisco's new shoes (a method of transporting drugs) into various shops and blowing up a rivalry factory, Cisco asks Mike to kidnap Yuka in order to bribe the Yakuza. Cisco then loses the services of Mike, who begins working for Asuka Kasen, and rescues Yuka from the Cartel.
However, Mike and Cisco do begin to work together again. Cisco attempts to find out who had killed Vinnie, but this only leads Mike into an ambush. Cisco moves from his home in Wichita Gardens to near Francis International Airport, to further his investigations. Cisco then has Mike distract a rival gang, whilst Cisco attends a meeting about the "bubonic plague". He pages Mike to say he has arrived safely, although he is killed by Vinnie, who had faked his own death. His unnamed lieutenant, actively tries to kill Mike, in order to extract revenge (believing that Mike was behind the near death of Cisco). The unnamed lieutenant is not Miguel, as the lieutenant can be killed, whilst Miguel appears in Grand Theft Auto III (set after GTA Advance).
Cisco is foolish and a bit cocky person, who keeps himself as much more intelligent than the people around him. Therefore he makes his orders as simple as possible when employing Mike.
Cisco is living in the United States, as he describes: "I am a proud, illegal alien and I have an identity card provided by the Mexican Government to prove it."