The Cursed Tribe

Background
"The orcs of Largashbur are beseiged by giants, and have been forbidden to leave their stronghold. Atub, the wise woman of the tribe, has asked me to find her Troll Fat and a Daedra Heart so that she may contact Malacath for guidance."

-Dragonborn

Quest Objectives
When you arrive at Largashbur there are some Orcs fighting a Giant, you need to kill the giant or simply watch the Orcs kill the Giant. Atub will start a conversation when you get near her, and the quest begins.
 * Bring a Daedra Heart and a Troll Fat to Atub.
 * Observe Atub's ritual.
 * Speak to Chief Yamarz.
 * Meet Chief Yamarz at Fallowstone Cave.
 * Protect Chief Yamarz.
 * Defeat the Giant.
 * Take Shagrol's Warhammer back to Largashbur.
 * Place Shagrol's Warhammer in the Shrine in Largashbur.

Walkthrough
Largashbur is an Orcish stronghold found near the Jerall Mountains in the south of the Rift region. As you approach the stronghold, the tribe of orcs will be engaged in battle with a giant. If Ugor, one of the orcs fighting the giant, dies entering the stronghold and starting the quest will be more difficult. If it is not possible to save Ugor, the stronghold may still be accessed by climbing the mountainside bordering the far left side of the entrance. Upon talking to Atub, the gate will unlock. Another alternative is to steal any of the equipment from Ugor laying on the ground. This will cause the Orcs to accuse you of stealing and they will unlock the door and come out of the stronghold. At this point the player can pay to gold as a fine and be able to enter. Additionally the Orcs will unlock the doors and come out to fight any wild animals, such as bears, that attack you near the gates. Finally, if the player has completed The Forgemaster's Fingers, the gates are unlocked.

The Orcs will initially be mistrustful of you. The one exception is Atub, speak with her to find out that her tribe has fallen on hard times. Chief Yamarz, the tribe's Chief, has become weak and cursed. The giants have taken advantage of this, assailing the stronghold regularly. Atub asks you to bring her Troll Fat and a Daedra Heart as an offering to Malacath, the patron Daedra of the Orsimer, in hopes that he might respond to the wise woman's prayers and guide the tribe in their time of need.

Retrieving the Ingredients
You can steal some troll fat from the shed with the Alchemy Lab to the right of Malacath's Shrine.Then, you can find a daedra heart adjascent from Kodlak Whitemane in Jorrvaskr in Whiterun (he's located downstairs). It appears that you may also find troll fat in the same room as the daedra heart in jorrvaskr, however it seems not everyone finds it there. Or if you have started the college of Winterhold questline you may talk to Enthir and get 2 Daedra hearts every 24 hours. Another way of gaining Daedra hearts would be to collect some during the part where you are still in Azura's Star. Daedric enemies spawn and you can collect their hearts to contribute to this quest.

Another easy way to find daedra hearts is if you've completed "Pieces of The Past" / obtained Mehrunes Razor*... two dremora (leveled to player) spawn outside of Mehrune's Shrine's (right in front of you when you fast travel there) and two more inside the shrine. The dremora respawn every 10 game days, making it rather helpful to get daedra hearts quickly.

The Ritual
Once you have given Atub the ingredients, she will insist that you observe the ritual of contacting Malacath. She will speak to Yamarz, who begrudgingly allows the ritual to occur. Malacath is displeased with Yamarz, who has allowed giants to overrun the Daedric Prince's shrine. The god demands that Yamarz bring him the giant leader's club as an offering; only then will he consider lifting the curse. Upon speaking with Yamarz, he will blame you for bringing this task upon him and tell you to join him at Fallowstone Cave, the entrance toward Malacath's shrine.

Fallowstone Cave
Meet up with Yamarz at Fallowstone Cave, located northeast of Riften. Be prepared to fight several giants, and possibly cave bears and trolls as well. You must protect Chief Yamarz as you travel through the cave until you reach the Giant's Grove on the other side. He is well equipped with full Orcish Armor and an Orcish weapon, and can handle himself well in battle. Still, he will find himself outmatched fighting giants by himself. Yamarz prefers melee attacks, so it may be best to hang back and pelt your gigantic enemies with arrows or magic while Yamarz fights up close. Be careful not to attack the orc Chief; it is easy to accidentally hit Yamarz as the two of you take on the giants. Attacking Yamarz will cause him to attack once no other enemies are present. You will need to load from a save that was before you hit him, otherwise he won't stop attacking you. If you decide not to load a save, you can continue through the quest and acquire the warhammer, anyway. If you do this and leave Yamarz in an area that needs a loading screen to get back to (i.e. going into Giant's Grove with Yamarz attacking you in the previous area) then he will become unkillable and will not stop attacking. Once you get the warhammer, it says to return it to the tribe like normal, but the quest marker to protect Yamarz never goes away.

Giant's Grove
At the Giant's Grove, Yamarz will ask you to retrieve the giant chieftain's hammer for him. He promises gold in return for your discretion; the tribe never has to know that their chief wasn't the one to return the giant's club Shagrol's Warhammer (if the Dragonborn refuses, Yamarz will attack the giant himself, and die quickly&mdash;"This'll only take a minute" are Ymarz's prophetic last words&mdash;and the Dragonborn must still defeat the giant). If the player decides to take the bribe and defeats the giant, Chief Yamarz will then attack the Dragonborn to ensure his tribe never learns of his cowardice. Regardless of the Dragonborn's choice, it is possible to sneak-kill the giant with a high sneak skill, the assasin's blade perk, the shrouded gloves, and a decent dagger. Thusly armed, it's possible to climb up the rocks of the shrine and get positioned right behind the giant without him noticing.

Malacath's Reward
After defeating the giant and taking Shagrol's Hammer from his corpse, return to Largashbur after defeating the giant. Atub asks for news of Yamarz, and Malacath will speak to the remaining tribesmen, telling them of Yamarz's treachery and weakness. Malacath gives the tribe a chance to prove themselves and appoints Gularzob the new Chief.

The daedric prince then rewards you for your worthiness, instructing you to put Shagrol's Hammer on his shrine. The hammer is transformed into Volendrung, the Daedric Prince's legendary warhammer.

The player can actually attain the Volendrun hammer at the end of the quest, once the headline appears that The Cursed Tribe quest is completed, the player can crouch and steal the Volendrun off of the shrine and keep it for themselves before Gularzob or another Orc removes it.

Ogol and Lob will be available as a followers upon completion of this quest.

Bugs

 * After putting Shagrol's Hammer on the shrine, it should be transformed into Volendrung, which will appear on the antlers of the deer skull on the shrine. However, there is a possibility that Volendrung will either drop off the antlers or not spawn at all. Make sure to look AT the antlers when activating the shrine, not looking downward, since Volendrung seems to spawn where the Dragonborn is looking.
 * If you forget to take Volendrung and then return to Largashbur, then Volendrung may be on the floor behind the antlers where it is supposed to be.
 * Sometimes upon reaching Largashbur, Ugor is dead on the ground but the glitch with everyone in the long house didn't happen. In that case, just speak to Atub, and she'll apologize for Ugor's harsh words, and start the quest that way, despite you never having met Ugor.
 * If looking around the shrine yields nothing, loading a previous save should cause Volendrung to spawn properly. Alternatively, just hit the altar and the stone a few times until the weapon pops out. Using the Unrelenting Force shout may also work.
 * Sometimes NPCs will respond as if you have already gone through the ritual when you reach the appropriate level for the quest. Even though his people act as if he is dead Yamarz is still alive. It is believed this happens if you enter the compound before the quest becomes available. If this happens the only fix is to load a save previous to entering the compound. If you do not load Volendrung is unattainable. This bug if not the cause is confirmed.
 * Initiating a dialog with sleeping NPCs in Largashbur Longhouse will not cause them to get up and speak to you as per normal, they will continue to sleep while talking.
 * After you start the mission, Yamarz will start his trek to the cave, you may follow him. As he makes his way to the cave, he might take a swim through the lake near Riften. If he does, and you follow, the PS3 will log you out of the game as if you quit from the center PS button.
 * Atub is nowhere to be found in the longhouse or anywhere in the area, this occurred when Ugor was dead.
 * NPCs appear to be stuck in the Longhouse and will not leave, move, or walk. Atub is missing and Ugor is dead. Two unidentified Orc bodies are found near or in the compound. This may be fixed by attacking an orc and leaving the longhouse, Atub may then appear to attack the player, simply pay the bounty and walk to her to begin the quest.
 * When first approached on your return, Atub is very hostile and demands what you, an outsider, are doing there, as if she had never seen you before. Talking to her jogs her memory.
 * If you enable all map markers via console and have not started this quest do not fast travel to Giant's Grove, you will not be able to fast travel out and will have to no clip through a blocked wall to gain entrance to Fallowstone Cave in order to get back to Skyrim. And if you kill the giant and take Shagrol's Hammer before starting the quest, the quest will start. If you start the quest this way it will break the quest and make it impossible to complete without using console.
 * If you follow Yamarz, he will take the path through Riften. The game may freeze if you go to the lake and swim around instead of entering Riften.
 * If you enter immediately after Yamarz he will not be in there, instead he will be outside not moving, only giving short responses.
 * Sometimes inside the cave the bears get stuck in the ground, being unable to be killed by you or Yamarz. This stops any progression towards the grove. Can be fixed by reload or using the Animal Allegiance shout or the Unrelenting Force (level 3) shout to get the animal unstuck.
 * After the battle between the Orcs and the giant ensues, upon first approaching Largashbur, Atub may not open the front gate and stand silently above the stronghold's wall. There is no way to speak to her from outside. A known way to resolve this glitch is to follow the fence toward the cliff wall on the right side. There is a spot where you can repeatedly jump until you're over the wall. The orcs will not be hostile, and you can now approach and speak to Atub. This bug may occur if Ugor is killed by the giant, and hence Ugor and Atub's conversation prior to opening the front gates cannot commence. Another fix is to hit Atub with an attack and when she comes down pay the bounty and you can enter freely.
 * When you kill the giant at Giant's Grove, it is sometimes only possible to loot it for the few seconds before Malacath begins to speak. This makes it impossible to complete, because you cannot obtain the giant's hammer. It is possible that this occures because you let the giant kill Yamarz, before you kill it.
 * If Ugor and the other Orcs are fighting the giant and you leave you come back to find all of the Orc guards and Ugor dead.
 * Sometimes no one is outside to start the quest. There is an opening in the gate near the goats, shoot an arrow at a passing goat and Atub will come out. (PC, 360 confirmed). If Yamarz is hostile towards you and you kill the giant at Giants Grove, when you return to largashbur and complete the quest, Yamarz might return to the longhouse and his dialogue will be the same as during the quest.(PS3 Confirmed).
 * It is also possible for Yamarz to not enter the cave and you have to clear the cave by yourself.
 * When exiting Fallowstone Cave to Giant's Grove, Yamarz may have vanished. The quest marker will be far to the east off the borders of the map, and using console commands to move to Yamarz's location or move him to the player will not work. The quest can still be completed however, kill the giant and take its hammer back to Atub, and the dialogue will proceed as though Yamarz fought the giant and was killed. While the quest will still complete this way, the objective "protect Yamarz" will still be unfulfilled in the quest entry.
 * It is possible that if you choose to fight The Giant for Yamarz, Yamarz can somehow become involved in the fight. The giant can be killed, and Yamarz will then attack you, however when his health reaches 0, he will crouch down, then get back up with full health, and cannot be killed, even if the hammer is picked up, or using the "kill" console command. To fix this use the console command "setessential 3bc26 0" (3bc26 being Yamarz' base ID, his reference ID displayed on screen will not work)
 * If Yamarz and the giant end up in a place where the giant's AI will not swing at Yamarz, it is possible for Yamarz to successfully kill the giant by himself. Since this was intended to be impossible, the game will believe that you have killed it; Yamarz will not return to the place he asked you to wait, and when you approach, he will speak as if you killed the giant and attack you.
 * Sometimes when you give Atub the ingredients she won't start the ritual. Reload to fix the problem.
 * If the chief is left in the cave he is still thought to be dead but will show up at Largashbur as if nothing had happened