The Tenno are the faction controlled by the players. Each player is a Tenno with a suit of biomechanical armor called a Warframe. The combat abilities provided by Warframes are vastly superior to both the Corpus' high technology and the Grineer's vast numbers; even the most inexperienced Tenno can fight their way through hordes of basic foot soldiers alone, and teams of experienced Tenno can best even the deadliest enemy threats.
Awakening from a deep slumber to a hostile world, the Tenno know little of themselves.
Each Tenno bears a primary weapon, a sidearm, and a melee weapon. Their arsenal includes rifles of various types, shotguns, pistols, swords, and exotic melee weapons such as staves, axes, and power gauntlets. Different Warframes offer their own unique powers, ranging from 's burst of superhuman agility to 's deadly avalanche. Also, Warframe armor's modular nature allows for major upgrades and wide customization options. Utilizing the arms, armor, and powers at their disposal, Tenno squads have adapted to wildly different situations using only a moment of downtime between missions.
At the height of their Empire's reign, the Orokin became embroiled in a war with the Sentients: a creation of theirs long ago sent to the Tau System to prepare for colonization, whose advanced technologies allowed them to quickly adapt to every attempt by the Orokin to defeat them. Each attempt by the Orokin to defeat the Sentients failed, so they turned in desperation to their last hope: the Tenno.
The Tenno were created in an incident long before the war, during the so-called "Void Era", when a ship called the Zariman Ten Zero became involved in a void-jump accident that sent it lost in the chaotic sub-dimensional space known as the Void. The ship reemerged from the Void and was recovered only days later, completely intact, but the only survivors found were children, whose exposure to the Void's energies had twisted and changed them, giving them inexplicable powers and abilities. Feared and reviled, the survivors of the Zariman nonetheless were of great interest to the Orokin.
Initial experiments on how to harness the children's powers though led to several fatal accidents, which showed the danger their uncontrolled powers could wreak both on themselves and on others. It was the work of an Orokin researcher named Margulis that led to a breakthrough; through dreams, the children could focus and control their powers. However, this research would then be taken from her after she was executed for trying to protect the children, and used to create a process known as Transference; the children's consciousnesses and powers could be remotely channeled through a surrogate body called a Warframe: a specially-made techno-organic humanoid battle frame designed to enhance and focus the children's powers, using a device known as a Somatic Link. The survivors would be placed in Somatic Link pods in a facility known as the Reservoir located on the Moon, to control their surrogate bodies in a secure location away from their enemies.
These operators, newly christened as the "Tenno", were taught the ways of war. With the combination of advanced technologies and esoteric powers, the Tenno began to turn the tide against the Sentients, allowing them to vanquish the Orokin's enemies across many battles.
The end of the Sentient threat should have been the end of the Orokin's struggles, but it was not to be. The Tenno since the beginning had always held a grudge against the Orokin for executing Margulis, whom they had always considered as their foster mother. And as the Orokin were celebrating their victory by bestowing the Tenno with honors, the Warframes struck, assassinating the Orokin's leadership and throwing the empire into chaos, an event that would herald the end of the Orokin Empire.
In the backdrop of the Orokin's collapse, the machinations of the Sentients continued; a plan had long been hatched to infiltrate the Orokin and destroy the Tenno. The agent given the task, named Natah, grew close to the Tenno she was supposed to destroy. Betraying her own kind, Natah used her considerable powers to hide the Moon within the Void, keeping the Reservoir and the Tenno they hold hidden from the Sentients, and the Warframes scattered throughout the Origin System were made to sleep in cryostasis. Natah, taking on the mantle of the Tenno's caretaker and guide, remade herself as the Lotus, keeping watch over the sleeping Tenno until the time they would wake once again.
- Main article: Category:Tenno Weapons
The Tenno have created a huge amount of "home grown" weaponry and equipment – much of it descended from Orokin counterparts, but some of it original. Tenno weapons, in general, tend to feature smooth lines, symbolic design, and an "organic" shaping that gives them a sleek, predatory look. Weapons of Tenno origin are among the most commonly available weapons to players.
- Main article: Lotus
Upon revival from stasis, the Tenno is guided by a figure known as the Lotus. Asserting preservation of her people by any means necessary, the Lotus dispatches and guides Tenno through missions of espionage, sabotage, defense, extermination, interception and rescue. On these missions, the Lotus guides Tenno using audio commands transmitted from an unknown location. Like the rest of Tenno culture, she remains shrouded in mystery, though the Natah quest sheds more light into her origins and motives.
Some weapons bear the Lotus emblem to distinguish them as being unique or Tenno-altered while other weapons bear the symbol simply as a trademark of Tenno construction.
Hostage Operatives liberated during Rescue missions are human and wear jumpsuits that bear the Lotus emblem, which indicates that the Lotus has many non-Tenno agents carrying out her orders. This is also indicated by her mention of various spy-cells and supply-raiding operatives, as well as the non-Tenno NPCs crewing the Relay stations.
- Main article: Orbiter
The Orbiters are spacecraft used by the Tenno to travel throughout the Solar System to and from missions. They also act as the Tenno's mobile base, carrying all of their various equipment and arsenal of weapons. An Orokin AI called Ordis acts as the main computer for the Tenno's ship.
- Main article: Focus
With the creation of Warframes, the Tenno founded five schools of combat that compliment various personalities and fighting styles:
- Madurai, School of the Fighters
- Vazarin, School of the Protectors
- Naramon, School of the Tacticians
- Unairu, School of the Indomitable
- Zenurik, School of the Arcane
- The plural of Tenno is Tenno.
- Tennō (天皇) in Japanese translates to "Divine Emperor". Additionally, in the Buddhist faith, the Four Heavenly Kings (四天王, Shiten'ō) are four guardian deities who watch over each cardinal direction under the leading "center" deity Indra or Taishakuten, and are the generals of the Hachi Bushu, the Eight Legions of Devas who protect and uphold dharma and virtue in the world.
- Probably owing to their inspiration, the Tenno are evocative of high sci-fi and henshin hero anime, manga, and Japanese video game concepts.
- The name "Tenno" dates back to the Hayden Tenno character from Digital Extremes's previous game Dark Sector. Warframe often uses concepts, art styles, names, and other materials from Dark Sector, due to it being a spiritual successor to the game itself. Since "Tenno" in this universe likely refers to the Zariman Ten Zero (or Ten-Oh), the ship itself was in some sense named after Hayden as well.
- Each Tenno behind the Warframes have official concepts and ideas to what they look like as stated by Art Director Mynki in Devstream 4.
- The Limbo Theorem and sources from DE have indicated that the Tenno have the ability to wear multiple Warframes.
- And further with The Second Dream showing that the Warframes are not worn at all, but instead commanded remotely by the true Tenno via a Somatic Link, at first in the Reservoir, and later in the Orbiter. However, Warframes do still have organic components, leaving open that human bodies may or may not inhabit them.
- How the Tenno switches between Warframes aboard the Orbiter is still somewhat unknown, as semi-independent creatures are stored as equipment long before the Operator knows what their selves are.
- The Grineer Queens in The War Within refer to Warframes as "infested puppets" and the Jordas Golem briefly confuses Warframes for fellow infested. This would indicate that infestation plays a large part in the organic elements of a Warframe and would also be the main reason why Warframes are immune to infestation (being already infested, the virus can do very little else to it).
- The Sacrifice quest suggests that the creation of Warframes involved infecting individuals with a modified strain of the Infestation. For example, was created by Ballas using a Dax soldier in this process.
- The Limbo Theorem and sources from DE have indicated that the Tenno have the ability to wear multiple Warframes.
- Possible note of worth, the Stalker refers to himself, and the others gathered around him as 'low guardians', making the distinction between the low guardians and the Tenno. It is possible that the Tenno were regarded as 'high', or the highest, guardians of the Orokin. From the in-game description of the Misa Syandana Prime, we also know that there were Temple Guards as well.
- In the Profit trailer, Alad V insulted the Tenno as "mute peasants" for humor, referring to the fact that Tenno have never been heard speaking verbally.
- This comment once led to speculation that the Tenno as a race may be mute, but with dialogue options with Simaris and Darvo now in the game, this theory seems to have been debunked.
- This theory has been completely debunked as of The War Within quest, where a cutscene shows a Tenno speaking to Teshin through their Warframe.
- 's Profile describes her existence as the result of "Tenno High Council" research, indicating that there is or was some sort of Tenno governing structure.
- The "Tenno High Council" may also just be a reference to the Design Council, a select group of players that can vote and provide opinions on concepts and designs made by Digital Extremes before they are released to the public. Nova was the first Warframe created from the Design Council's input.
- Loading screens mention quotes by Tenno Councillors with two-letter names.
- In the prologue added in Update 14.0 (2014-07-18), Vor states that the Ascaris is nearly attached to the Tenno's spine. This implies that Tenno are biological and possess at least some biological structures that are analogous to those present in humans.
- The Second Dream quest reveals that Warframes may contain a surrogate body inside, that is capable of withstanding Tenno powers. This would explain the "attached to the spine" quote.
- The Sacrifice further details this by stating that the Infestation strain used to create Warframes causes the organs of the host to restructure, gaining strength beyond steel, so it is possible that the "spine" - and other organs as such - still exists in a materially transmuted form. However, this is the case primarily for Excalibur Umbra, who is also seen to still have eyes and a face within his damaged helmet; as Excalibur Umbra was still an experiment in Warframe genesis, it remains to be seen whether later Warframes, including ones piloted in the present day by the player, still contain such easily recognizable structures, or indeed if they are still made using human hosts and not something more easily converted, in which case the "spine" may be more analogous than literal.
- Xaku is a composite Warframe created from the parts of three other Warframes. Their 4th ability, The Vast Untime, causes them to shed the "skin" of two of their components, revealing a skeleton underneath. This shows that, indeed, Warframes do have skeletons analogous to human skeletons. In addition, Xaku's skull has visible eye-sockets, suggesting that all Warframes may have vestigial eyes underneath the surface of their skin, not just Umbra.
- Previously, there was much debate about whether the "player character" was a single Tenno switching frames or multiple Tenno, each with their own personal frame (ala an MMO character select screen, all individual but all technically existing at the same time).
- Since the release of The Limbo Theorem and Ordis asking the Operator (the player character) to exercise caution when they "occupy this frame" it can firmly be said that the player is a single Tenno and that they are indeed switching Warframes.
- Shortly after this reveal there was some debate about whether or not Ordis was breaking the fourth wall, but in a Reddit AMA Steve confirmed it was not.
- The Second Dream quest reveals that Warframes are remote-controlled battle stations, definitely containing techno-organic elements inside (as was mentioned by Lotus "the surrogate, capable of withstanding Tenno powers"; meanwhile the Operators have the ability to take control of one Warframe at a time via Somatic Link or direct connection (touch).
- Also, all or most of the early in-game Defense missions use a "WARFRAME CRYOPOD" which was presented as life-support pod, contained humanoid beings in jumpsuits, similar to one, that Relay Personnel and Syndicate's Agents wear. This fact may or may not suggest, that cryopods held the surrogates, who were made for use in "Tenno-Warframe"-link.
- The Tenno seem to sit in 'kiza' position, a form of Japanese sitting style. This form is used in Japanese sword schools and martial arts as a sitting position from which an attack or defense can be mounted.
- In Update 18.0 (2015-12-03), the full name of the ship which housed the children who would become the Tenno was finally revealed though there were no prior indications that the full name had not already been disclosed in the codex entry for .
- Upon closer examination, there is a play-on-words with regards to the full name of the ship, and the origins of the Tenno themselves. The ship had been directly referenced by partial name once before, in the codex entry of Ember Prime, as the Zariman. However, this leaves out the Ten-Zero portion of the name after it, i.e. Zariman Ten-Zero. The hidden reference is most easily apparent in English, because of a linguistic shorthand used to refer to the number 'zero', with the shorter identity of just "O". This can be seen in pop culture, such as in the title of the TV show "Hawaii Five-O".
- Upon shortening Ten-Zero into 'Ten-O' – and to make it easier to pronounce, combining the syllables into one word – 'Tenno' – it becomes even more plainly visible that the Orokin (as a society) were truly unnerved by the children who had been found on the ship. They wished to maintain such a clinical attitude towards the children that they simply named them – as a group – after the very ship they were found on.
- Tenno have faces?
- "I watched from a distance, with the rest of the low Guardians." - Stalker/Shadow Stalker's Codex entry
- "Discovered in the vaults of a drifting derelict, this Syandana was worn by Temple Guardians before the fall of the Orokin Empire." - Misa Prime Syandana description
- DE Developers Talk on Reddit