Kings' Gambit

Kings' Gambit is a main quest in Fallout: New Vegas.

Synopsis
Ambassador Crocker is concerned that the New California Republic is merely tolerated in New Vegas; there have been issues between NCR citizens and Freeside locals, and the ambassador seeks an end to it.

Detailed walkthrough
Once you have completed the quest Things That Go Boom, speak to Ambassador Crocker, who will assign Kings' Gambit. Crocker tells you about all the violence in Freeside being caused by the Kings. He gives the Courier two options: solve the problem diplomatically, or kill Pacer, the main person responsible for the violence.

Option: Kill Pacer
If the player character has already talked to the ghoul Rotface, he may have given them tips, two of which include the fact that Pacer has a heart problem and too many drugs will kill him. Another tip states that he has a feud with the Van Graff family. If the Courier has not talked to Rotface, this option can also be opened by stealing Pacer's treatment records from Julie Farkas' filing cabinet in the Old Mormon Fort. This will add two optional objectives to the quest, one to kill Pacer by adding Psycho to his jet (requires 60 Medicine) and the other is to kill Pacer in a way that implicates the Van Graff family. One must to do this before his stash appears.

Method: Frame the Van Graff family (Jean-Baptiste Cutting's note)

 * 1) Examine Pacer's stash of jet which is disguised as a carton of cigarettes under his bed, (then try to take it, a prompt will appear stating that one should obtain a note to pin the blame on someone else), then return to Ambassador Crocker.
 * 2) Talk to Ralph at Mick & Ralph's and ask him to forge a handwritten note written to Pacer from Jean-Baptiste Cutting. (he will only do this if the player character has a high enough Speech skill [50] or if the Kings have accepted them, and if Rotface tipped the player character about the feud between Pacer and the Van Graffs)
 * 3) Go to Pacer's room (first room on the left, third floor of the King's School of Impersonation).
 * 4) Replace Pacer's stash of jet with the handwritten note.
 * 5) When Pacer checks his stash, he will immediately run over to the Silver Rush and get himself killed.

This method works even if the player character killed everyone in the Silver Rush building earlier. Just follow Pacer there after planting the note in his room and kill him with a plasma or laser weapon to frame Van Graffs.

It is important to talk to The King before returning to Ambassador Crocker.

If the Courier does not see any progress on this quest after leaving the note, head to Silver Rush and watch Pacer get killed.

Method: Frame the Van Graff family (working as a guard)

 * 1) Start the quest Birds of a Feather.
 * 2) While working as a guard, when Pacer comes and talks to the player character, pick a fight with him by using hostile dialogue options such as the third option in the first dialogue and "Care to back that up?" in the second. This will make him hostile.
 * 3) Kill him with the energy weapon given by the Van Graffs.

Doing this won't make the Kings hostile and will make the Courier successfully complete both Kings' Gambit (since the player character killed him with an energy weapon while working for the Van Graffs) and Birds of a Feather (killing him doesn't make the player character fail this quest).

However, killing Pacer will break the quest line G.I. Blues, therefore it is recommended finishing that quest first.

Method: Frame the Van Graff family (planting energy weapon)

 * 1) Wait in or around Pacer's room until night time.
 * 2) Sneak into his room and pick his pocket, planting a plasma grenade or mine on him.
 * 3) Back up REALLY quickly.

Doing this will off Pacer in a way to frame the Van Graffs, so the player character will still get the rewards from the Ambassador, and the Kings will not suspect them.

Note: The player character must first go back and talk to the ambassador (after they speak with Rotface) first before planting the plasma grenade/mine. Otherwise, Pacer will never go to sleep in his room.

Method: Spike the jet with Psycho
To complete this method, either speak to Rotface and give him caps until he tells the Courier about Pacer's addiction or check the filing cabinet in Julie Farkas' wing of the Old Mormon Fort. One must also first speak with Ambassador Crocker and tell him their plan, which requires a [60] Medicine check. It will then add an optional quest to kill Pacer using his jet. Follow these steps: Note: killing Pacer in any way will immediately fail the quest G.I. Blues, so if One wants a favor from The King, they need to finish G.I. Blues before killing him.
 * 1) Go to Pacer's room (the first room to the left on the third floor of The King's School of Impersonation)
 * 2) Add the Psycho to the stash of jet under his bed (roughly between 8A.M. and 9P.M.). The stash is disguised as a carton of cigarettes, but it will only appear AFTER speaking with Rotface or looking through Julie Farkas's files (see above).
 * 3) Pacer will die by checking his stash in his room during the night (the earliest time he can be found in his room is about 7P.M.)
 * 4) Pacer will die immediately when he checks his stash.

Method: Just kill Pacer
Using an energy weapon to kill Pacer will allow one to accomplish this quest, however using any conventional weapons will result in failing the quest. If the latter is the case, the player character will still get a reward (if they apologize) and are still allowed to move onto the next quest. If the player character wishes to easily regain fame with Freeside, go to the Atomic Wrangler and talk to James Garret regarding spreading positive rumors about the Courier in Freeside. One will have to pay more caps depending on how infamous they are.

Option: Solve diplomatically
If the favor from G.I. Blues has not yet been used, the Courier can ask The King to stop the violence and turn the quest in. However, if it has already been used, the King will say no and one must return to Ambassador Crocker to tell him that the King will not stop the violence. Crocker will then propose two options (on top of the option to kill Pacer): Talk to Colonel Moore at the Hoover Dam or talk to Colonel Hsu at Camp McCarran.

Method: Colonel Moore

 * 1) Head to Hoover Dam and talk to Colonel Moore, who asks the Courier to tell the Kings to stand down or be destroyed. She also offers to send a squad for backup.
 * 2) Anything said to The King in this option will cause him to refuse and a fight will break out. The quest will fail when Crocker is told what happened. However, no Freeside infamy will be gained if one lets the troopers do all the shooting. The King's unique suit can be obtained in this path, as well as a reward of 300 caps from Crocker if one apologizes and gets to move onto the next quest. If Rex has not been obtained as a companion at this time, he may be killed by the NCR.

Method: Colonel Hsu

 * 1) Go to Colonel Hsu at Camp McCarran and tell him about the situation in Freeside and he will tell the Courier to offer the King support from the NCR.
 * 2) Upon returning to the King, tell him the NCR have offered their support. If one is rude to him, his gang will open fire and the quest will fail. He will also open fire if one just tells him to calm down, taking it as a challenge. Like with Colonel Moore, the King's unique suit can be obtained here, as well as a reward of 300 caps from Crocker if one apologizes and gets to move onto the next quest.
 * 3) If the Courier is polite, the King agrees to peace with the NCR, but Pacer will become angry and will attempt to stage a coup within the Kings, and he and a few Kings gang members will start a gunfight with the NCR troopers, the King, and the Kings loyal to him. Pacer and the men who side with him are killed and the King goes ahead with peace between the Kings and the NCR.

After this, return to Crocker.

Note: If one attacks Pacer or any other Kings, even after they turn hostile and open fire, it may result in a gain of infamy with Freeside and both groups of Kings as well as the King himself turning hostile. The best way to avoid this is to let the NCR troopers and any companions do the shooting, which results in no infamy gained for the player. Pacer and his men are heavily outnumbered by the NCR troopers alone, meaning there is little chance the King will die in the gunfight. Additionally, there was originally going to be an opportunity to pass a Speech check of 75 and talk Pacer down from staging the coup. This was cut from the game and can only be restored through the use of mods on the PC version of the game.

Reward
The player will be rewarded with 1300 XP, 600 caps and NCR fame. With 60 Barter, another 200 caps can be gained. In addition, the quest For the Republic, Part 2 will begin. The player character will get neither of these if Pacer is merely murdered.
 * Received 1200xp and had an option (with a Barter skill of 60) to ask for more caps (200). Diplomatic solution, using a favor from The King.
 * Received 1200xp, received 600 caps and had an option (with a Barter skill of 60) to ask for more caps (200). Spike the jet with Psycho solution.

Behind the scenes

 * In chess, the Kings' Gambit is an opening strategy where a pawn is sacrificed in exchange for rapid development and control of the center.
 * It was believed that Elvis Presley died of a drug-induced heart attack due to underlying heart problems, much like how Pacer dies if his drug stash is tampered with.