A Prime Warframe, Weapon, Sentinel, or Accessory represent Orokin technology, as it was during the height of the Oroking Empire Era. While they are technologically superior and display better stats compared to their modern counterparts, these forgotten pieces of the past are scattered all over the Origin System, waiting for the Tenno to recover them.
What are the Prime Items?
In-game, the term Prime refers to any Weapon, Warframe, Sentinel, Archwing, or accessory made with Orokin technology, which the non-Prime variants are based upon. Primes frequently show better Polarity slots and stat changes that grant them a slight advantage over their normal derivatives.
Prime Warframes are usually released respecting the Warframe's order of release, cycling between two male frames and two female frames. Each release is accompanied by two Prime weapons, or one Prime weapon and one Prime Companion or Archwing. These releases come as drops in-game, obtainable by opening Void Relics, or alternatively in the game shop in the form of various cash packs, called Prime Access.
Void Relics & How To Obtain Prime Items
Void Relics are objects that can be opened by finishing Void Fissure missions. They are the principal means of acquiring Prime Items and Forma Blueprints, as well as Ducats from exchanging Prime parts in Relays. These are received as rewards in missions (usually Endless missions), and at least one relic is guaranteed from completing any mission in the Void.
Void Relics have four different tiers with different possible reward tables, named as follows:
Lith - B8, C7, C8, D4, G3, I1, P5, T4, T5, T6
Meso - C6, D6, I1, K3, N11, P2, P4, R4, T4
Neo - B7, K3, N13, N14, N15, P2, T2, V9, Z7, Z8
Axi - A11, A13, C6, G5, O5, S8, T6, V10, W2, Z1
Void Fissures, also known as Void Storms in Empyrean missions, are a type of mission in which players can open Void Relics and obtain the items within them.
These present as normal missions, but in addition to the mission's assigned objectives, Void Fissures will appear across the map, spawning Corrupted units from the Void as well as converting nearby native enemies into Corrupted units.
When this happens, one of the spawned or converted enemies will drop a Reactant, which the players must collect 10 of for the Relic to crack open. Is at this point that the player can complete the mission and receive their reward, and they will be awarded 6-30 Void Traces at extraction, a resource used to refine Void Relics to make them increase the drop chance of the rarer rewards.
Prime Vault & Unobtainable Prime Items
The Prime Vault is the conceptual “archive” that houses items that have been retired from the game's reward tables. When an item is “vaulted” it means that players are no longer able to acquire Void Relics that can potentially reward those items. However, any item that the player already owns will not be removed from their inventory if they are to be vaulted.
Several times a year, the Prime Vault will “open”, bringing back Items that can be reacquired in limited-time Prime Vault Packages, offering retired Prime items and Prime Access-exclusive accessories, at the cost of real-world money. The prime Warframe and weapons parts included in these packages will be also re-added to the game’s drop tables through new relics until it closes again.
Excalibur Prime - The Exception
Excalibur Prime is the Prime variant of the Warframe Excalibur, possessing higher armor and energy, as well as additional polarities. He is a Founders-exclusive Warframe, released alongside Lato Prime and Skana Prime. All of them are currently and permanently unobtainable, since the founders' program closed on the 1st of November, 2013, thus making Excalibur Prime no longer available.