For the book of the same name, see Kagrenac's Tools (book).
Kagrenac's Tools are the legendary artifacts crafted by the Dwemer Tonal Architect Lord Kagrenac. Each tool served a specific purpose to siphon the power of the Heart of Lorkhan, via tonal manipulation of the laws of nature.
The gauntlet Wraithguard was created to safely wield the weapon tools, Sunder and Keening. Wielding the weapons without the gauntlet will often lead to the instant death of the wielder. Wraithguard also functions to empower the abilities of Keening and Sunder. Accounts of its appearance vary,  but it typically looks like a gauntlet made of a material comparable to brass. It is also known as the Wraith Mail.
The short blade Keening (also referred to as the ethos knife) was created to flay and focus the power that the hammer Sunder produced. In song, its described as a dagger made of the sound of the shadow of the moons.
The Creation of the Tools, The Disappearance of the Dwemer, and the Ascension of Almsivi
At some point by the early First Era, Dwemer miners discovered a mysterious, magical stone beneath Red Mountain. The Dwemer Tonal Architect Lord Kagrenac determined that this stone was the Heart of Lorkhan, and constructed the tools to harness its powers. His goal was to create a new god for the Dwemer—Anumidium. This god took the form of a colossal brass golem called Numidium, and was the key to the Dwemeri bid for ascension, be it godhood, immortality, or something greater.[UOL 1]
By some accounts, Kagrenac constructed Anumidium without the knowledge of the Dwemer King Dumac. The Chimer learned of it, however, and Dumac's claims of innocence when confronted by his friend Lord Nerevar sparked the War of the First Council. The war culminated around 1E 700 with the Battle of Red Mountain; while again accounts vary widely, most agree that Nerevar, Dagoth Ur, and others made their way into the Heart Chamber beneath the Dwarven citadel.
In the ensuing battle, Kagrenac (or Dagoth Ur, by Azura's instruction) used the Tools on the Heart of Lorkhan, which caused the Dwemer to immediately vanish from Nirn. Nerevar died. (or was murdered) Soon after, the Tribunal took possession of Kagrenac's tools, and used them to siphon the Heart's power and ascended into living gods. Thereafter, they made an annual pilgrimage to the Heart Chamber to recharge their powers.
Dagoth Ur Awakens
In 2E 882, Dagoth Ur awakened, and ambushed the Tribunal during their annual pilgrimage to Red Mountain to renew their divine powers. The event resulted in the Tribunal being cut off from access to the Heart of Lorkhan. The Tribunal then launched intermittent campaigns to assault Red Mountain to force access to the Heart Chamber, and two of the three tools, Keening and Sunder, were lost during a campaign in 3E 417. The weapons were then split among two different Ash Vampires, with Dagoth Odros guarding Keening within the citadel of Odrosal, and Dagoth Vemyn guarding Sunder within the citadel of Vemynal.
Sotha Sil's Tools
The loss of the Heart led the Tribunal God Sotha Sil to develop his own variant of the Heart of Lorkhan, the Mechanical Heart. To siphon the Mechanical Heart's power, Sotha Sil created his own variants of the Tools to control, shape, or even dismantle it if necessary. He foresaw his eventual death at the hands of Almalexia, and eventually hid his tools as a precaution across Nirn to prevent the Heart's power from being stolen. The location of the tools was lost after his demise—though some tales describe a Forgotten Hero reclaiming them Circa 4E 201.
The Destruction of the Heart of Lorkhan
In 3E 427, an outlander sent by Emperor Uriel Septim VII arrived in Vvardenfell, and was believed by many to be the reincarnation of Nerevar—the Nerevarine. After many trials, and towards the end of their journey, the Nerevarine was ready to head into Red Mountain. They recovered Wraithguard from the Tribunal God Vivec, and assaulted the Sixth House citadels to obtain Keening and Sunder. During their final battle with Dagoth Ur, all three were used to destroy the enchantments on the Heart of Lorkhan, after which it seemingly disappeared from the world, destroying Dagoth Ur and Akulakhan in the process.
The Tools' Journey to Skyrim
All three tools would eventually leave the collection of the Nerevarine. By 4E 5, Sunder and Wraithguard found their way into the hands of a group of smugglers, who attempted to smuggle them through Skyrim and into Hammerfell, using the refugees fleeing the effects of the Red Year as cover. Once out of Morrowind, Dwemer Animunculi began attacking their caravan. Unknown to them, the Tools had a fail-safe system implemented within them in order to prevent the Tools from ever leaving Morrowind. The fail-safe was a signal indicated by a tuneless and quiet singing that activated a Tamriel-wide network of drones, which sought to retrieve the Tools if they were taken out of Morrowind. After retrieving the Tools, they would then deposit them in a vault until a Tonal Architect could come and retrieve them. Seeking to put a stop to the attacks, some of the caravan captains betrayed their employer and handed Sunder and Wraithguard over to the drones. A scholar working under the same employer oversaw the delivery of the cargo, and learned of this, and managed to track the items in the snowy wastes southwest of Winterhold, to a vault located in Sightless Pit. She became trapped within it and died before an expedition could be organized to find her.
In 4E 201, Keening found its way into Skyrim when the mage Arniel Gane requested the delivery of it for research. By this time, the blade was no longer dangerous to wield without Wraithguard. Keening was briefly lost along the way when the courier died. Arniel used the blade on a warped soul gem to reproduce the events which led to the disappearance of the Dwemer; unfortunately, the experiment was a success, and Arniel vanished. The blade then passed into the possession of the Last Dragonborn, who had aided Arniel in his endeavor.
Later that year, the Dragonborn learned of the whereabouts of Sunder and Wraithguard's location and traveled to the Sightless Pit. There, they navigated the various traps and battled the vault's guardian, a Dwemer centurion which appeared to be made out of an ebony alloy. They then retrieved Sunder and Wraithguard, and united all three Tools once again. The Dragonborn discovered that like Keening, Sunder lost its enchantment which killed its wielder without the use of Wraithguard.
- Kagrenac's Tools appeared in TES III: Morrowind, and in TES V: Skyrim. Sotha Sil's versions appeared in Legends.
- Kagrenac's Tools — Gilvas Barelo
- Baladas Demnevanni's dialogue in Morrowind
- Wraithguard item in Skyrim
- Events of Morrowind
- Five Songs of King Wulfharth
- The 36 Lessons of Vivec — Vivec
- Nerevar at Red Mountain — the Tribunal Temple
- Progress of Truth — Dissident Priests
- Yagrum Bagarn's dialogue in Morrowind
- The Battle of Red Mountain — Vivec
- Dagoth Ur's Plans — Tribunal Temple
- Haft-Shard of Sunder contraband item in ESO
- dialogue in the mission The Tools in Return to Clockwork City
- Dialogue in the mission The Throne Aligned in Return to Clockwork City
- Legends's Return to Clockwork City story
- Events of the Skyrim Creation Club quest Legends Lost
- Events of Skyrim
Note: the following references are not from official sources. They are included to provide a rounder background to this article, but may not reflect established lore.
- Skeleton Man's Interview with Denizens of Tamriel, The Imperial Library