The Satellite Square: Etherion (衛星魔法陣・エーテリオン Eisei Mahōjin : Ēterion), best known as Etherion (エーテリオン Ēterion), is an extremely powerful Magic Weapon controlled by the Magic Council. After the Magic Council's complete destruction at the hands of Tartaros, Etherion has been completely neutralized.
Tower of Heaven arc
Stated to be a nation-destroying Magic that is capable of transcending space-time, Siegrain tricks the Magic Council into firing Etherion at the Tower of Heaven (in order to gather the 2.7 billion Edeas of Magic Power required to activate the R-System), by stating that Jellal plans to use the Tower of Heaven to resurrect Zeref. After a session of re-voting, during which the Magic Council voted to use Etherion (much to Yajima's chagrin), the preparations to fire Etherion begin, which take one full hour. It is fired after a group of Mages under the Council's control chant an incantation, ending with "We pray to the sacred light, Release Etherion!!", causing a series of glyph-like circles and squares to appear above the Tower of Heaven. Once the preparations are finished, a blinding beam of light is shot down, decimating all in its path until it hits the Lacrima crystals inside the Tower of Heaven, which absorb its energy, successfully turning the Tower of Heaven into the R-System. Natsu later eats the Etherion-infused Lacrima of the R-System, prompting him to enter Dragon Force.
Alvarez Empire arc
A member of the Spriggan 12, Wall Eehto, transforms into the dangerous Assault Mode in order to kill the extremely powerful Laxus Dreyar. During the ensuing fight, after severely debilitating his foe with a wide array of attacks, Wall reveals that he has the capacity to fire a concentrated Etherion blast as a cannon from his palm, which he describes as being able to completely eradicate Laxus. However, Wall chooses not to fire his Etherion, as Laxus puts up a Jutsu Shiki barrier, which prompts him to disengage his cannon and prioritize his safety and the Jutsu Shiki barrier's nullification first. After nullifying the barrier, Wall accidentally ends up nullifying the Magical Barrier Particles within Laxus' body as well, and is defeated by the affliction-cured Mage, leaving Etherion ultimately unused.
Etherion, once successfully prepared, fires an extremely large, destructive beam of Magic upon the desired location (said Magic contains Fire Magic, among other elements), that completely obliterates the target area, leaving only dust behind.
- Natsu Dragneel, a Dragon Slayer (who can restore his energy by eating his specific Element), was able to eat Etherion and enter the ultimate state a Dragon Slayer can attain: Dragon Force; even though Etherion is fused with elements aside from fire. The consumption of the other elements, however, left Natsu incapacitated for days.
- Etherion shares its name with the Ultimate Magic in Hiro Mashima's earlier work, Rave Master. It shares the same destructive capability as its namesake.