Rex (Fallout: New Vegas)

The '''Mk. III Cyberhound, LEO Support Model, Serial no. B955883, known to the people of Freeside as Rex''', is a cyberdog in 2281 under the ownership of The King. He is suffering from neural degeneration as a result of his old brain.

Background
Part German Shepherd, Rex is a "cyberhound Mk III law enforcement officer support model" that has been around since pre-War times. He was born as a regular dog in 2072 and served in the Denver City Police Department. Sometime before the war, he was cybernetically enhanced and turned into a cyberdog - serial no. B955883, although the circumstances of his cybernetic alterations remain unknown. He survived the destruction of Denver and the harsh wastelands, eventually becoming Caesar's companion for a time, but was lost in battle. He later reached Freeside, where he came under the ownership of The King, who loves him dearly. Rex does not like rats, or hats, according to The King. The King says his dislike of hats may come from the fact that hat rhymes with rat.

Quests

 * Nothin' But a Hound Dog: The player has to find a replacement brain for Rex by taking him to Dr. Henry in Jacobstown.
 * You'll Know It When It Happens: Rex can sniff out the disguised assassin for the player without having to search around for him.

Other interactions

 * The Courier can replace Rex's brain to prevent him from dying as a result of neural degeneration.
 * If the player has the Wild Wasteland trait, Rex will say "aroo" to the courier at a random time. The Courier can then ask if Jimmy has fallen down a well (this is random and does not always happen). This adds the location Jimmy's well to your map. Down in the well you will be confronted by a mole rat, and there will be a skeleton. Next to him is the Abilene Kid LE BB gun, 2 tins of BB's, a super stimpak and a rawhide cowboy hat. This is a reference to the television series Lassie, as well as to the quest with Laddie in Fallout 2.

Endings
{| class      ="va-table" ! # ! Voice-over narration ! Description of the scenes ! In-game condition



Appearances
Rex appears only in Fallout: New Vegas.

Behind the scenes

 * Rex's companion arc was designed by Jesse Farrell.
 * Rex is Latin for "king", which relates to his owner's name.

Bugs

 * In the course of the quest Nothin' But a Hound Dog, it is possible to stealthily kill Lupa and loot Lupa's brain from her corpse. If she is successfully killed without the player being noticed, Antony may not "notice" that Lupa has died and will still give you the option to fight her in the arena for her brain. If the player accepts, it is possible to obtain a second Lupa's Brain. Having two of the brains in your inventory will cause Dr. Henry to not recognize that you have the brain at all, making it impossible to give Rex Lupa's brain. To solve this, either revert to an earlier save, or enter in the console. Make sure that you only have one instance of Lupa's brain.
 * When Rex is ordered to return to the Lucky 38 presidential suite, sometimes he will not be there.
 * Sometimes simply entering the King's School of Impersonation will cause Rex to appear near The King and will start running to the Lucky 38. The player can chase and intercept Rex or wait until he returns to the presidential suite to recruit him.
 * Rex loses health when near the Remnants bunker. Fast travel to some other place if you see his health drop.
 * If you dismiss Rex during Nothin' But a Hound Dog, when he is theoretically on loan to you and not a permanent companion, he may disappear and not return to The King. He may eventually show up after traveling to Doc Henry and speaking to him about Rex. Alternatively, you can enter to get Rex to appear, then get talk to him to get him to follow you.
 * During combat, Rex might chaotically run around from-and-to foes while not attacking anyone. He may also in fact not attack at all when you have him.
 * Rex will sometimes stop moving as if he has been told to wait. You will need to keep checking to see if he is still with you. This can usually be fixed by telling him to wait, then tell him follow you again, fast traveling or going through a door that requires a transition. However these fixes are per incident and he will randomly do it again.
 * This appears to occur if the player stands around in the same spot for too long. Rex will then sit down and wait around.
 * While doing the quest You Can Depend on Me (or just trying to sneak into the Gun Runners), Rex may glitch while in combat with the guards and end up in the Vendortron's kiosk. There is no physical way into the kiosk and Rex can still be spoken to. The only way to fix this problem is to fast travel to another location, in which Rex will appear beside you in patched versions of the game.
 * While vilified by the Legion, if Rex simply kills Lupa while you are disguised and have her brain transplanted by Calamity, the epilogue may state that Rex never got a replacement brain even though the quest is completed, rather than the correct ending.
 * When you are knocked out in Dead Money when you escape, you might not be able to find Rex anywhere.
 * If Rex and another person (i.e. the player or another companion) attack the same enemy at the same time and the game goes into slow motion kill-cam, the game may freeze. Turning kill-cam off may solve this problem.
 * On pc if Rex is running to attack an enemy and you or another companion kill this enemy while Rex is charging, the game will CTD with a visual c++ runtime error.
 * If you tell Rex to wait outside when visiting Caesar in the quest Render Unto Caesar and you confirm that you want to battle Benny, the game will automatically send you to the ring, and when you win, Rex will be nowhere to be found. He isn't with The King or at any casinos. If you were already at the point in Nothin' But a Hound Dog where you are looking for a new brain, you can still gain a brain as the AI will think you still have Rex, but when you go back to Doctor Henry, he will say he can't perform the surgery without Rex. To fix this in the PC version open the console and type - Rex is located next to the arena along the outer fence. To recover Rex on Xbox, you can go to Vault 22, fix the elevator (requires Repair 50) and use it to go to the 5th floor.
 * When acquiring Rex from The King in his room, very top floor of The King's School of Impersonation, he will sometimes drop through the floor and wind up at the bottom level. Just wait a few minutes and you will find him running towards you.
 * For some reason Rex may just randomly die, even outside of hardcore mode.
 * While in combat with an enemy, shooting Rex may cause the game to freeze.
 * Initiating conversation with Rex, while in the water, may cause a the game to freeze/crash.
 * While Rex is a companion, the game sometimes freezes when he attacks an enemy.
 * While at the Lucky 38 with other companions, Rex will sometimes start to fight them. There is no known fix for this. He may also do this with Quartermaster Bardon at Hoover Dam.
 * When told to go to Lucky 38 he might appear next to The King.
 * On rare occasion Rex will begin to growl uncontrollably as though there are enemies nearby. He will continue to do this even after you load a new location. It seems that this sometimes happens when you load a previously saved game while Rex is in the middle of attacking an enemy. The only known way to solve this problem is to send Rex to the Lucky 38 and then recruit him again.
 * Sometimes, the people around you in a location will attack Rex until he is unconscious (casual mode). They will not be hostile to you, only Rex. Fast traveling will stop the attacks for a while, but not indefinitely.
 * Sometimes giving Rex weapons will cause them to disappear next time his inventory is opened.