Antagonist

Antagonists, or simply enemies, are the main villains of the Grand Theft Auto games. The antagonist of a GTA game is usually a person that has betrayed or hurt the protagonist on a personal and social level, and spends the game moving against the protagonist in multiple ways.

Description of Most Antagonists

In the GTA games, the main antagonist is introduced at the very beginning of the game, but as a ally or friend. Sometimes, the antagonist is the main reason that a protagonist visits the city/state. In most GTA games with antagonists, they usually fake a friendship or business relationship with the protagonist then suddenly, in one mission, reveal their hate for or double cross the main character and begin to open fire on them with a weapon. The main character always hunts down and eliminates the antagonist eventually, usually in some big event at the end of the game.

Antagonists usually have a gang behind them for protection. The main character will battle the antagonist group and sometimes take them over.

Grand Theft Auto III

Catalina (main antagonist)

Antagonist Group: Columbian Cartel
Killed in: The Exchange
Reason: Betrayed Claude during a bank heist.

Miguel (antagonist)

Antagonist Group: Colombian Cartel
Killed In: Ransom.
Reason: Told Cartel secrets to Asuka Kasen so Catalina attacked and killed them both.

Salvatore Leone (antagonist)

Antagonist Group: Leone Family
Note: Salvatore provided work for Claude and eventually sold him out to the Colombian Cartel, however Claude manages to escape.
Killed in: Sayonara Salvatore
Reason: Assasinated by Claude as ordered by Asuka Kasen to prove his loyalty to her.

Grand Theft Auto: Vice City

Sonny Forelli (main antagonist)

Antagonist Group: Forelli Family
Killed in: Keep Your Friends Close
Reason: Shot dead by Tommy Vercetti for betraying him 15 years ago and sending him to prison.

Lance Vance (antagonist)

Antagonist Group: Vance Crime Family
Killed in: Keep Your Friends Close
Reason: Betraying Tommy and siding with Sonny Forelli to possibly take down Tommy together and dominate Vice City.

Ricardo Diaz (antagonist)

Antagonist Group: Diaz Gang

Killed in: Rub Out
Reason: Set up a drug deal causing Harry, Lee, Victor, to die, plus stealing the money, and drugs.

Grand Theft Auto: San Andreas

Frank Tenpenny (main antagonist)

Antagonist Group: Tenpenny is/was a member of the Community Resources Against Street Hoodlums, otherwise abbreviated as C.R.A.S.H., who is working out of Los Santos, San Andreas.
Killed in: End of the Line
Reason:Was the reason GSF members sided with Ballas, and possibly threatened some to join him.

Eddie Pulaski (antagonist)

Antagonist Group: Pulaski is/was a member of the Community Resources Against Street Hoodlums, otherwise abbreviated as C.R.A.S.H., who is working out of Los Santos, San Andreas.
Killed in: High Noon
Reason: Crashed in the Las Brujas.

Big Smoke (antagonist)

Antagonist Group: Ballas and Los Santos Vagos
Note: Big Smoke is an O.G in the Grove Street Families but he betrayed the gang and he worked with Tenpenny and Pulaski, along with the Ballas.
Killed in: End of the Line
Reason: Killed by CJ for betraying him and the Grove Street Families, and for killed Sweet´s and CJ´s moms.

Ryder (antagonist)

Antagonist Group: Ballas and Los Santos Vagos

Note: Ryder is an O.G in the Grove Street Families but he betrayed the gang and he worked with Tenpenny and Pulaski, along with the Ballas.

Killed in: Pier 69

Reason: Killed by CJ for betraying him and the Grove Street Families.

Grand Theft Auto: Liberty City Stories

Massimo Torini (main antagonist)

Antagonist Group: Sicilian Mafia
Killed in: The Sicilian Gambit
Reason: Started the wars between the mob families, which caused the Leone's to lose some ground.

Miles O'Donovan (antagonist)

Antagonist Group: Police

Killed in: Not Killed

Reason: He assisted with the cops for Salvatore Leone's arrest.

Vincenzo Cilli (antagonist)

Antagonist Group: Leone Family (Rival to Toni)
Killed In: The Portland Chainsaw Masquerade.
Reason: Attacking Toni with an SMG and chainsaw-wielding madmen.

Grand Theft Auto: Vice City Stories

Jerry Martinez (main antagonist)

Antagonist Group: Similar to Tenpenny, Martinez is a corrupt Sergeant for the United States Army and is not in any gang. He does however have control over some gangsters in Vice City that try to kill protagonist Vic Vance, but they are not an official gang.
Killed in: Last Stand
Reason: Possibly setting him up, and sending hitmen after him.

Diego and Armando Mendez (antagonists)

Antagonist Group: Mendez Cartel
Notes: The Mendezes are the powerful drug cartels in Vice City. However, they want all businesses of Vic and knock Vic and Lance out but all their efforts fail to kill the Vance Brothers.
Killed in: Armando in Light My Pyre and Diego in Last Stand.
Reason: Killed Louise Cassidy Williams.

Grand Theft Auto IV

Dimitri Rascalov (main antagonist)

Antagonist Group: Russian Mafia

Killed In: A Dish Served Cold (Revenge) or A Revenger's Tragedy (Deal).

Reason: Killed for selling out Niko to Ray Bulgarin, burning down Roman's taxi company, and Niko's house, and for arranging Roman's kidnapping.

Jimmy Pegorino (antagonist)

Antagonist Group:  Pegorino Family

Killed In: Out of Commission (Revenge)  or A Revenger's Tragedy (Deal)

Reason: Killed by Niko for killing Kate McReary (in revenge), or killed by Dimitri Rascalov out of disloyalty (in deal).

Darko Brevic (antagonist)

Antagonist Group: None

Can be killed in: That Special Someone

Reason: Can be killed by Niko Bellic for betraying him, Florian Cravic and the rest of the fifteen men who were killed back in the war. Though he can be spared.

Grand Theft Auto IV: The Lost and Damned

Billy Grey (main antagonist)

Antagonist Group: Former President of The Lost Brotherhood before being arrested.
Killed In: Get Lost
Reason: For attempting to rat out Johnny Klebitz, Angus Martin, and pretty much the rest of the club.

Ray Boccino (antagonist)

Antagonist Group: Pegorino Family 
Killed In: Pest Control (GTA IV).
Reason: Tried to control the Lost Brotherhood, was responsible for Jim Fitzgerald's death and convinced Billy Grey to rat out Johnny and Angus.

Notes: He was killed by Niko in GTA IV for Jimmy Pegorino who believed he was ratting out the Family.

Brian Jeremy (antagonist)

Antagonist Group: Brian's Chapter.
Killed In: Bad Standing or Brian Jeremy (Random Encounter).
Reason: Killed by Johnny for attempting to kill him, Jim Fitzgerald, Terry Thorpe, Clay Simons and some loyal bikers on Johnny's side.

Grand Theft Auto: Chinatown Wars

Wu Lee (main antagonist)

Antagonist Group: Lee Family
Killed in: Salt In The Wound
Reason: Killed by Huang for killing his father.

Grand Theft Auto: The Ballad of Gay Tony

Rodislav Bulgarin (main antagonist)

Antagonist Group: Russian Mafia.
Killed in: Departure Time
Reason: Killed by Luis for trying to kill him and Gay Tony.

Rocco Pelosi (antagonist)

Antagonist Group: Ancelotti Family
Killed in: Not Killed
Reason: Extort Anthony "Gay Tony" Prince and tried to kill him.

Notes: A mademan of Giovanni Ancelotti