The Reality Stone is one of the six Infinity Stones, the remnant of a singularity that predated the universe, which represents the fabric of reality. Liquefied into a dark red fluid called the Aether (pronounced ēTHər), the Dark Elves and their leader Malekith intended to use it to revert the universe to its state of primordial darkness. The Aether was taken from the Elves by the Asgardians and entrusted to the Collector following the Second Dark Elf Conflict.
During the Infinity War, the Aether was retrieved from the Collector's Museum in Knowhere and solidified by the Mad Titan Thanos, who put the Stone inside his Infinity Gauntlet. After collecting the rest of the Infinity Stones, Thanos used the complete Infinity Gauntlet to snap his fingers, causing half of all life in the universe to crumble into dust. Upon fleeing to the Garden, Thanos would ultimately destroy the Reality Stone along with the rest of the Infinity Stones to avoid being tempted to use their powers and to ensure that the Snap became irreversible.
In 2023, the Avengers conducted a Time Heist in order to resurrect the lives Thanos had claimed, with Thor and Rocket Raccoon sent back in time to 2013 to retrieve the Aether from Jane Foster. Following the Battle of Earth, where Iron Man used all six stones to kill Thanos and his army at the cost of his own life, Captain America time-traveled to Asgard of 2013 to return the Reality Stone, albeit in its solidified state.
Powers and Stats
Tier: Unknown, higher in conjunction with the Convergence
Name: The Reality Stone, The Aether
Age: As Old as the Big Bang
Classification: Infinity Stone
Powers and Abilities: Reality Warping (The Reality Stone can manipulate reality), Energy Manipulation and Projection (Can generate blasts and tendrils of dark energy), Illusion Creation (Can create highly elaborate physical illusions of false realities, including of living beings that can physically interact with others), Invisibility (The Stone's illusions can make its users invisible), Matter Manipulation & Transmutation (Gave Thanos the power to warp and transmute matter into anything he wished, most often using this ability to transfigure and use objects around him offensively. The Aether can convert matter into dark matter), Biological Manipulation (Can warp the bodies of a living organism), Animal Manipulation (Thanos transmuted the pieces of a ship that he destroyed into a countless swarm of bats that he sent towards Iron Man), Earth Manipulation (Thanos used the Reality Stone to spawn a cage of stone pillars to trap Black Widow), Life-Force Absorption (The Aether can sapp the life energy of its hosts), Creation (After Malekith's own hands were cut off, the Aether created a new pair for him), Vibration Manipulation (Capable of sending out shockwaves filled with its energy and pulses of power that can throw back any who it deems a threat to itself on its own), Dimensional Negation (Thanos was able to prevent himself from being trapped inside the Mirror Dimension by a gateway to said dimension sent at him by Doctor Strange with the Reality Stone), Power Bestowal & Statistics Amplification (Malekith, fused with the stone, was on par with Thor in terms of raw strength and the Stone granted him various powers), Size Manipulation (Caused Malekith to grow in size to roughly three times Thor's height), likely others
Attack Potency: Unknown (One of the Infinity Stones, which are said to be some of the most powerful artifacts in the universe, and should be comparable to other Stones like the Space Stone), higher in conjunction with the Convergence (When used during the Convergence, the Aether can turn all matter in the realms into dark matter and plunge everything into darkness, however this is a process done over time)
Speed: Massively Hypersonic+ (Can react to Thor's and Iron Man's attacks)
Durability: Unknown (Thanos needed to use the Infinity Stones to destroy the Space Stone)
Range: Dozens of meters via Energy Projection, Universal in conjunction with the Convergence and the other Stones
Weaknesses: The effects of the Stone last only as long as the wielder is actually present in the area, and the original reality reasserts itself immediately afterwards at least for some of its abilities, otherwise none notable.