Frost/Prime

Frost Prime features an additional  polarity slot, but has an otherwise identical slot layout to Frost's. The blueprint for Frost Prime was attainable from the Fusion MOA event, and is now currently attainable from the Orokin Void along with its components.

Acquisition
Frost Prime Warframe Blueprints were distributed to anyone that participated in the Fusion MOA Army Extermination Operation, on the condition of at least one Fusion Moa kill, which lasted from 3 May 2013 through to 5 May 2013.

Currently, Frost Prime's blueprint and its components can be acquired from the Orokin Void.

Trivia

 * Frost Prime is the second Prime version of a Warframe and the first to be craftable.
 * The Blueprint for Frost Prime was given out by an extermination event that completed on May 5, 2013.
 * Frost Prime has a secret interaction with Box Traps. Upon approaching one, it will replenish your energy by 100 points and the swirling energy in the Death Orb will change to just black. This can only be done once per Box Trap. This is true for all Prime Warframes.
 * Similar to Excalibur Prime, Frost Prime is able to use the alternate helmets (Squall Frost Helmet & Aurora Frost Helmet as well as the default Frost Helmet)
 * The technology oriented by Frost Prime is related to the Orokin technology used to keep the Infestation in stasis, which could be why Frost's release as the first collectible Prime is reasonable as the lore stated to be scavenged by the Tenno as they advance throughout the Solar system.