Umbriel Crisis The Umbriel Crisis was an event that threatened Tamriel during the Fourth Era . Black Marsh and Cyrodiil were the most affected provinces , although Morrowind was also involved in the conflict . Background . After Vivec ' s disappearance , the Ingenium was built to keep the Ministry of Truth afloat . The Ingenium needed souls to be powered . At first , it consumed as much as ten souls per day . Criminals were used to power the ingenium , but eventually , a Vuhon discovered that appropriate souls could power it for months . He selected a Dunmer named Ilzheven to power the Ingenium . Ilzheven ' s man , Sul , thought that Vuhon had selected her because she loved him instead of Vuhon . Sul tried to save Ilzheven , but he destroyed the Ingenium and killed Ilzheven . The explosion hurled Vuhon and Sul to Oblivion . The ministry crashed into Vivec City , triggering the events of The Red Year . Vuhon and Sul ended up in Clavicus Vile ' s realm . A being named Umbra took them captive . Umbra had become an independent being from the eponymous sword , and he had somehow managed to cut a piece from Clavicus Vile himself , stealing a lot of power from him . Vile circumscribed his realm against Umbra so that he couldn ' t escape . When Vuhon and Sul came to his realm , Umbra took advantage of the situation and threw the blade through the rift they had entered from . Vuhon made a deal with Umbra , he offered him to build a new ingenium so that Umbra and him could escape from Vile ' s realm . Sul managed to get away from Umbra , he wandered through the different realms of Oblivion trying to return to Tamriel . Since Umbra couldn ' t leave Vile ' s realm , Vuhon managed to wrap Umbriel , Umbra ' s city , in a Oblivion bubble . Vuhon and Umbra merged into one being who could control Umbriel at their will . The only thing Vuhon / Umbra , henceforth called Lord Umbriel , needed to break free from Vile was to go to Tamriel in their bubble and use the power of the White - Gold Tower to free them . Lord Umbriel made a pact with Hierem to summon Umbriel into Tamriel and allow him to use the power of the White - Gold Tower . In exchange , Hierem could overthrow Emperor Titus Mede I and become the new emperor . Hierem made a trip to Lilmoth and performed a ritual in the Hist of the city to summon Umbriel . The An - Xileel allowed him to perfom the ritual as long as Umbriel only killed non - Argonians and Lukiul ( the assimilated ) . Summoning . Umbriel , the flying island , was summoned in the southwest of Black Marsh . It approached Lilmoth through the sea . The flying city was followed by an undead army that murdered the population and destroyed the city . The deaths supplied Umbriel with the souls needed to power the Ingenium . One of the only survivors of the massacre were Annaïg Hoïnart and Mere - Glim . They drank levitation potions that brought them to Umbriel . Annaïg was decided to save Tamriel from the incoming threat , so she sent a message to Prince Attrebus warning him about Umbriel . Annaïg gained the trust of the Umbrielians and worked in the kitchens of Umbriel in order to keep Prince Attrebus informed about anything she could discover about Umbriel . She eventually was promoted to chef , even preparing a meal for Lord Umbriel himself . Ambush on Prince Attrebus . Attrebus Mede was a hero to the people . When he received the message he informed his father about Umbriel . Titus had already received reports about the flying city , but according to the reports , in was heading to Morrowind . He would not send an expedition to stop it unless it threatened the Empire . Attrebus did not pay attention to his father , so he secretly prepared his men for an expedition . In their march to Umbriel , they were ambushed by a criminal organization hired by Hierem to kill the prince . However , Radhasa , the leader of the ambush decided to keep Attrebus alive and sell him to a eccentric Khajiit in Elsweyr . During their journey , Radhasa revealed to Attrebus that all his guards knew he was a mediocre warrior , and certainly not a hero . His father had risen him to believe he was a legendary hero , and Attrebus had believed so . Umbra and Vivec City . Sul , who after serving Azura had managed to return to Tamriel , received a vision from the Daedric Prince . Azura warned him about Umbriel and hinted him to find Attrebus , so that he could avenge Ilzeheven . Sul rescued Attrebus from Radhasa . Sul explained the prince all he knew about Umbriel . He expected that Umbriel would head to Vivec City to recover Umbra sword , the only artifact capable of defeating Lord Umbriel . In order to beat Umbriel to Viven City , they had to take a shortcut trough Hircine ' s Hunting Grounds . They were aided by they F ' aashe clan , who sacrificed so that Sul and Attrebus could escape from Hircine . Once in Vivec City , Sul searched for Umbra . He encountered with Ilzheven ' s ghost , who warned him that a Dunmer who wore a signet ring with a draugr had already taken the sword . Umbriel arrived at Vivec City , and the zombies captured both Attrebus and Sul . They talked to Vuhon , who revealed them that he was now heading to the Imperial City . Sul tried to kill Vuhon , but it was useless without Umbra . He opened a door to Malacath ' s realm , and Attrebus and him escaped from the flying city . Solstheim . Attrebus and Sul were healed by Malacath . Sul deduced that the Dunmer who had taken Umbra must be in Solstheim . They convinced Malacath to send them to Solstheim . They discovered that the man who recoved Umbra was Elhul Sathil . He went mad as soon as he touched the blade , so his father had to lock him up in the depths of their castle . Attrebus and Sul had to kill Elhul . Once they owned the sword , they were summoned by Clavicus Vile to his realm . Clavicus demanded them to return him his sword . Yet , they needed it to defeat Vuhon and stop Umbriel . They made a bargain with the prince to allow them to defeat Umbra and return him the power he had stolen from him . In exchanche , Vile demanded a soul , but Attrebus refused to the additional requirement . After all , Vile needed their help as much as they needed him . Cyrodiil . Umbriel razed everything in its path . The fallen men and women were resurrected as zombies , thickening Umbriel ' s army of undead . Cheydinhal was sieged by the zombies , but the city guard and the legionaries that had withdrawn to the city opened a gap in the enemy line so that the citizens could evacuate . Once the citizens evacuated the city , Captain Arges ordered to split into two groups , one north and one south of the Blue Road , and hope the main army of zombies didn ’ t come after both of them . The zombies headed to the Imperial City . General Takar lead the last attempt to stop Umbriel from attacking the Imperial City . He commanded five thousand men , mostly mounted infantry and mages , and eight siege engines . He launched an attack on Umbriel , half of the legion suddenly left the ground , along with the engines , and flew toward the city . The attack was repelled by flying creatures , and Takar retreated to the Imperial City . Siege of the Imperial City . Vile sent Attrebus and Sul to his shrine in Cyrodiil . The approached the Imperial City by boat . They were captured by Hirem ' s agents . Inspector Colin Vineben , a member of the Penitus Oculatus who had been tasked to investigate Attrebus ' pretended murder and who discovered that Hierem was involved in the Umbriel Crisis , received a report that claimed that Prince Attrebus had been seen at the waterfront . He was abducted , taken away with a bag on his head . Colin and Letine Arese , an agent of the Emperor who had worked in Hierem ' s ministry for ten years and gained his trust , broke in Hierem ' s chambers . They rescued Attrebus and Sul , and they designed a plan to stop Vuhon and Hierem . Hierem was finalizing the plan to attack the Imperial City with Vuhon in Umbriel . Attrebus and Sul waited for him in the sigil he used to teleport . When Hierem came back to his chambers , Attrebus and Sul were teleported to Umbriel . Colin and Letine fought Hierem , who died ripped by a daedra summoned by Arese . Arese stabbed Colin with her knife and she headed to a room that was in the very axis of the White - Gold Tower . She had discovered that Hierem intended to become a god draining the power of the tower and using the power of the souls in Umbriel . Letine had suffered for ten years , and she wanted to something in exchange , to feel safe again . Colin recovered from the stab and stopped Arese from performing the ritual . He hit Letine in the eye with the knife he had nailed in his body , ending with her life . Colin died of his wounds shortly after . The imperial soldiers made a massive push toward the northwest side of the city . That was where the enemy was massed most deeply , and had begun actively trying to break through the gate that led to the Imperial prison . It was also where Umbriel would arrive , if it continued on the course it was presently following . The left flank collapsed , and the zombies threw themselves on the city wall , building ladders with their bodies . Annaïg poisoned the trees in Umbriel to weaken Vuhon . Sul tried to use Umbra on Vuhon , but the sword did not seem to work . Annaïg warned Sul and Attrebus that Lord Umbriel ' s soul was in the Ingenium . Attrebus wielded Umbra to destroy the Ingenium . Umbra briefly possessed Vuhon ' s body before being trapped in the sword . Just then , Clavicus Vile possessed Attrebus , Vile demanded a soul for their bargain . Sul sacrificed to save Attrebus from Vile . Umbra and Sul melted together with the Ingenium . Aftermath . After the Ingenium was destroyed and Vuhon was defeated , the zombies became inanimate . Attrebus spared Vuhon ' s life so that Mere - Glim could avoid Umbriel from falling into the Imperial City . Glim lead Umbriel into the Realm of the Hist . Attrebus gave credit of the victory to The Synod and The College of Whispers , who had cooperated to stop Umbriel , in order to start their reconciliation and have their political support now that Hierem was dead .