Barbas appears outside of Falkreath upon first visiting the city, or during the middle of The Break of Dawn. One of the guards or Lod will direct the Dragonborn toward Barbas, who needs help locating his "master". Following the talking canine to Haemar's Shame, the Dragonborn discovers Barbas is the pet of Daedric Prince, Clavicus Vile. The Dragonborn can choose to kill Barbas for Vile in exchange for the Rueful Axe, or choose to reunite Barbas with this master and recover a powerful Daedric artifact. Additionally, should the Dragonborn choose to recover the axe and postpone doing so, Barbas can become a permanent and invincible follower.
After returning Barbas to Clavicus Vile, the Dragonborn can return to Lod for a small reward by telling him "The dog was more trouble than he was worth".
Barbas is one of the quest characters that can be exploited to follow the Dragonborn throughout Skyrim along with an additional follower. The downside of this is that since he isn't technically a follower, he'll trigger the detection "eye" while sneaking, making stealing very difficult, because the player can't tell who has spotted them and will give a bounty if Barbas sees the crime. You can, however, tell him to "stay" before attempting any tricky stealth activities.
Barbas is a useful follower to have in a fight since his bite is strong enough to kill many weaker enemies in one strike, and he's an effective decoy against more powerful enemies, because he cannot be killed during the course of game-play. Even if he were to sustain enough damage in a single attack to kill him, he will not die, but instead he'll flee, then return to the fight immediately when healed.
His barking, as with any dog follower, is incessant, but it does not alert enemies.
He maintains a very close proximity, frequently bumping into the Dragonborn; any attempts to stop may result in him shoving the Dragonborn, making many basic actions difficult, including boxing the Dragonborn into corners, or worse case, shoving off cliffs or narrow walkways. This can be solved by hitting Barbas with a weapon once, where he will back off and whimper.
In Oblivion, Barbas's statue guides the player to find the Umbra sword. He first tells the player to go to Pell's Gate. When the sword is acquired, return to Clavicus Vile's Shrine and either give the sword to Clavicus, or keep it and have all of his followers attack instead.
PC 360 PS3 If the Dragonborn chooses to follow Barbas to the shrine, his route through Helgen will see some bandit attacks take place - this may cause Barbas to do a second run through in Helgen.
PC 360 PS3 As Barbas comes to the Helgen gate that requires opening by the Dragonborn, the opening of the door tends to slam Barbas against the wall. The player must close, then reopen it to let him through.
PC 360 PS3 If one decides not to kill Barbas and talk to him before he gets turned into stone, the whole statue of Clavicus Vile will disappear and Barbas will remain in the room forever. He will no longer follow or respond in any way, but remains stuck in the party restricting the ability to recruit any dog companions thereafter.
PC 360 PS3 Lod, the blacksmith, may be dead, but the quest can still show up.
PC 360 PS3 If the Dragonborn decides to follow Barbas through Helgen, and the main exit is locked, Barbas might start climbing the door erratically because he can't follow his scripted path. If the door gets unlocked during the process, Barbas might get stuck behind it, causing the game to crash.
PC 360 PS3 Solution: To prevent this issue, if the door isn't unlocked before the pursuit, one can still get it open by reaching it before he does or during a fight with bandits, since Barbas cannot be killed at that point. The Dragonborn can also unlock the door and then close it again, and somehow Barbas will open the door himself.
PC 360 PS3 Barbas is invincible when one tries to kill him and does not take correct actions.
PC 360 PS3 Barbas can sometimes go through the metal gate behind the Clavicus Vile shrine and start fighting the boss vampire behind it.
PC 360 PS3 Sometimes, when approaching Haemar's Shame, it won't say onscreen that it is discovered, but it is possible to fast travel to it.
PC 360 PS3 Barbas does not show up at his quest marker after speaking to Lod.
PC 360 PS3 Solution: To avoid this glitch complete any misc quest (e.g. treasure hunt quest) involving Rimerock Burrow before speaking to Lod about the dog. Clearing Rimerock Burrow will not affect the quest to retrieve The Rueful Axe.
PC 360 PS3 Entering Haemar's after retrieving the Rueful Axe can cause random objects to spawn in the cavern.
PC Telling Barbas to wait inside Rimerock Burrow may cause him to disappear at the moment the Dragonborn takes the axe.
PC 360 PS3 Barbas may get lost on the path to the statue. In the moments the final dialogue is completed and Barbas becomes part of the statue, he may never actually catch up, which in turn disables the ability to have a follower.
PC 360 PS3 Barbas can get stuck inside Broken Oar Grotto. Please refer to that page's bug section for the PC version console command fix.
Even when A Daedra's Best Friend is completed, the game will sometimes still show Barbas as an animal follower. This will prevent the Dragonborn from getting another animal follower.
PC Using the console command "set PlayerAnimalCount to 0" will clear the animal follower state and allow the Dragornborn to acquire a new animal follower.
360 If the Dragonborn attacks Barbas before going to Haemar's Shame, using Command Animal will make Barbas continue on his path (until the spell wears off). This can be done at Clavicus Vile's Shrine, before speaking to him for the first time. Barbas will not be hostile towards the Dragonborn now.
360 Barbas will sometimes glitch and randomly become hostile to any follower. If the follower is in the essential faction, the two will constantly fight.
360 Solution: Reloading the last save wil fix this.
Barbas may appear randomly after any transition.
If player ignores Barbas at first sight, and Lod is dead due to Dragon attack on Farkreath, quest is unable to start.