Aeion

Aeion (pronounced ay-on) is a "very mystical and powerful energy source" introduced in Metroid: Samus Returns. As a complement to her Chozo equipment, Aeion gives Samus various extra abilities. The Scan Pulse is one such ability, which allows Samus to see hidden blocks, and expands the visible Map on the 3DS's lower screen. Multiple Aeion abilities can be used at once, although it obviously means a larger consumption of Aeion.

To collect Aeion abilities, Samus must visit Aeion Ability Artifacts. To replenish Aeion, Samus can collect Aeion Orbs dropped by enemies after they are killed or when some bosses are damaged. She can also fully replenish Aeion by finding Big Aeion Orbs or by revisiting Aeion Ability Artifacts or Chozo Statues. The capacity of Samus's Aeion Gauge is increased by collecting Aeion Tanks. Aeion Abilities are activated by pressing A, and deactivated by pressing A again. Holding A for 3 seconds deactivates all Aeion Abilties at once. Selection of Aeion Abilities is done with the Control Pad.

The fanfare that is heard when an Aeion Ability is acquired is a remix of the Chozo Artifact collection theme in Metroid Prime.

Upon acquiring the first Aeion ability, Samus is given a default capacity of 1000 Aeion. Obtaining each subsequent Aeion ability increases this amount by 150. Additionally, each Aeion Tank increases her capacity by 50, so the maximum possible capacity for Aeion is 2200 (discounting the Aeion Reserve Tank, which refills her Aeion Gauge to 500 if depleted).

Origin and implications
The origin of Aeion is stated to be a powerful energy created by planet SR388 itself. This energy seems to have been absorbed into the planet's life forms, as observed by its release upon every creature's death and its emphasis in the second Chozo Memory. The third and seventh memories depict Chozo mining operations with heavy focus on yellow light being emitted from dig sites.

Interestingly, the eighth Chozo Memory shows the same yellow light which emanate from cracks on the ground shining brightly upon the Metroids as they molt out of their larval phase. Aeion may thus be the factor that triggered the species to metamorphose into uncontrollable forms, leading to the collapse of the Chozo civilization on SR388.

Strangely, Aeion is also present in all of the planet's robots and Proteus Ridley, the latter of whom is an off-world entity. While the robots' Aeion may be the result of the Chozo energizing their machines with the collected energy, Proteus Ridley acquired his via unknown means.

The SR388 Data File trailer states that the Galactic Federation believes Aeion to be linked to the Chozo.

Metroid: Samus Returns Manual
As you progress in the game, you will be able to use up Aeion energy stored in your Aeion gauge (p. 7) and perform special abilities.


 * You can activate multiple abilities at once.


 * Aeion Ability
 * "The currently selected ability is designated by a white frame. Abilities will light up when in use."


 * Aeion Abilities Screen
 * "Check current Aeion abilities and their effects.
 * Press [R] to switch back to the map menu screen." 

On-screen tutorial
"Aeion fuels special abilities, like the Scan Pulse. Refill your gauge with the Aeion Orbs foes may drop when you either beat them or successfully parry."


 * Notification
 * "Upgrading suit for Aeion compatibility..."

List of Aeion Abilities

 * Scan Pulse - Expands map and scans environment
 * Lightning Armor - Prevents physical damage and increases range of Melee Counters
 * Beam Burst - Enhances the currently equipped beam's attack power and enables rapid-fire shots
 * Phase Drift - Slows down time

Trivia

 * Aeion's possible origins as an energy created by SR388 and how the planet fills its inhabitants with its energy, is akin to Earth's natural background radiation.
 * Proteus Ridley may have obtained Aeion energy by devouring life forms found on the planet, as Ridley is known to regenerate and strengthen himself by consuming flesh.