Excalibur/Umbra

"Ferocious and untamed, Umbra’s fury is second only to his mastery of the blade."

- Introduction of Umbra

Excalibur Umbra is the Umbra variant of Excalibur, sporting higher armor and energy, as well as three polarities while losing a. Unique to Umbra is its display of sentience, allowing it to fight on its own when not piloted by the Operator.

It first released in the Chinese build of WARFRAME. It was later added in the Global build in, and can be acquired through The Sacrifice quest.

Acquisition
The blueprint for Excalibur Umbra is given to players upon completing the first mission of The Sacrifice quest, and the ability to build the Warframe is granted on completing the second mission. Unlike other Warframes, Umbra requires no further components and is constructed entirely from the single blueprint. However, even after being crafted, Umbra cannot be used until the penultimate mission.

At the end of the quest, players will receive Excalibur Umbra at rank-30 with a free, pre-installed Orokin Reactor, and Warframe slot.

The Sacrifice
"But you won't have to imagine. A lovingly cultured Infestation swarms within your blood. Your transformation has begun, reshaping you into a sacred surrogate of the unholy Tenno... A Warframe with but a Single. Burning. Memory. It is... a miracle! But all miracles require sacrifice."

- Ballas

Excalibur Umbra was originally an Orokin Dax soldier who was punished by Ballas for attempting to interfere with his betrayal. The soldier was deliberately exposed to the Infestation to become an anti-Sentient weapon, a "miracle" that requires "sacrifice", then psychologically tortured into rote obedience by forcing him to kill his son, Isaah.

As a result of Umbra's torment, he retains most of his sentience and is capable of acting on his own without the Tenno's control, even initially rejecting the Operator's Transference and going rogue. Umbra also carries the memories of his final moments before transforming into a Warframe, which the Operator discovers to contain codes that unlock Ballas's Vitruvian recordings of the Sentient's betrayal, the creation of Warframes, and the Tenno.

"--We had created monsters we couldn't control. We drugged them, tortured them, eviscerated them... We brutalized their minds... but it did not work. Until they came. And it was not their force of will - not their Void devilry - not their alien darkness... It was something else. It was that somehow, from within the derelict-horror, they had learned a way to see inside an ugly, broken thing-- And take away its pain."

- Ballas

After seeing all of Umbra's memories, the Operator reassures Umbra that they will fight Ballas together. Upon seeing this act of compassion, Umbra calms down and finally accepts the Operator's Transference.

Trivia

 * Umbra is the Latin word for "shadow".
 * Excalibur Umbra is the first Umbra variant of a Warframe to be released in WARFRAME.
 * Excalibur Umbra is the only quest Warframe that cannot be purchased from the Market or be sold.
 * Excalibur Umbra's agile and noble animations are the only animations that are able to be used on other Warframes without prior purchase.
 * In the Chinese build, Excalibur Umbra originated as part of their Founder's pack exclusive, as Excalibur Umbra Prime, gameplay-wise identical to Excalibur Prime. The pack also included the Nikana Prime and the Spira Prime (both of which were introduced in the Global Build with Saryn Prime instead), as well as the Gauvan Prime Sekhara, a shoulder accessory obtainable only through that Founder pack.
 * Excalibur Umbra Prime is still purchasable for players of WARFRAME (China).
 * Upon release, Excalibur Umbra had the passive ability of Prime Warframes to gain energy from Orokin Void Death Orbs, as an erroneous leftover from his data origins as Excalibur Umbra Prime. This was later removed in.
 * Umbra utilizes a different sword design for his Exalted Blade, which is named Exalted Umbra Blade. The stats for both weapons are identical however.
 * Upon completion of The Sacrifice quest, players will receive an Excalibur Umbra-exclusive Excalibur Umbra Sunder Helmet in their inbox, which is a battle-damaged version of the regular Umbra helmet.
 * Excalibur Umbra is the first Warframe confirmed to originally be a human. It is also the first frame to have had its face exposed due to damage to its helmet.
 * Ballas confirms that Warframes are created from human subjects as Infested-hybrids cultivated by the Helminth.
 * When interacting with Baro Ki'Teer, Baro will treat Umbra as he would any other Prime frame.
 * Umbra's scarf and torso lining, along with his Orokin ornaments, remain visible when other Excalibur skins are equipped, similar to the Prime details of Prime Warframes when using TennoGen skins.
 * Both Stalker and Shadow Stalker use a unique variant of Excalibur Umbra's body, which lacks the Orokin ornaments and Umbra's signature scarf, and has a different loincloth design.
 * Unlike other Warframes, Umbra cannot be affected by it's own Operator's Protective Dash from the Vazarin Focus school. This is likely related to its sentience during Transference.
 * Possibly related is the fact that Umbra's Operator's Protective Dash can affect their own Companion. This is not the case for other Warframes.
 * Excalibur Umbra's roar was voiced by DE Steve