Vision has always been an invaluable member of the Avengers, but when trying to define everything he can do, it's easy to see just how weird his body gets. Though he was created by the villainous Ultron as a tool for the Avengers' destruction, he soon became one of their most powerful members who underwent recurrent cycles of discovery with his humanity and inhumanity. With a foot in both worlds, not quite man and not quite machine, it's time to narrow down the five absolute strangest things about Vision's body.
The Vision's Density Sometimes Makes Him the Strongest Avenger
Perhaps the most valuable ability in Vision's arsenal is his ability to alter his density, with his control over his molecular structure so complete and so minute that he can move his atoms closer or further away from each other. When he pulls them apart he decreases his density, allowing him to fly and even "phase" his molecules through solid objects. When he draws them closer he can pull in the molecules around him to increase his mass and density, making him an unbreakable heavy object that can smash meteorically into the Earth.
This allows Vision to, at least for brief spurts, become one of the strongest and most durable Avengers on the entire super team. Maintaining such heightened states can be strenuous and require an excess of power, so Vision rarely keeps himself at such a level consistently.
Vision’s Phasing Is as Good an Offense as It Is Defense
Shifting his molecules works in the other direction as well. Vision can decrease his density to allow himself to phase into other objects, but what's truly awe-inspiring is that it need not always been a defensive move -- it can also be an attack. While Vision's go-to defense most frequently involves phasing through his attackers' offense, rendering physical force useless against him, he can also turn the tables by shifting his hand into his opponent and partially increasing his density to semi-phase with their molecules.
The result is agonizing pain, often rendering his foe unconscious in a matter of moments. The phase attack creates molecular interference with the atomic state of his target and it's actually pretty gruesome when one imagines an android hand just partially appearing inside their nervous system.
The Vision's Synthezoid Cells Can Rebuild Him
Building up from the molecular level, Vision is perhaps even more unique on the cellular level. Vision is not a typical robot; he's a synthezoid, meaning his body is artificial but mimics many biological processes. Such a biological structure lends itself to something analogous to cells that compose Vision's body, an example of nanotechnology that is astonishingly advanced even by Marvel's standards.
Such a structure allows Vision to encode much of the data composing his consciousness into every individual cell. With his schematics backed up so thoroughly, the survival of even a shred of Vision's body allows him to be rebuilt almost perfectly following devastating destruction. Vision's been no stranger to such destruction over the years, but he always comes back with a new body and the same moral fiber that makes him more than an appliance.
The Vision's Immune System Impressed Ant-Man
The pseudo-biology of Vision's body allows him to regenerate like a living creature would and for his body to defend itself with a series of obstacles quire similar to an immune system. When Ant-Man and some of his insectoid companions endeavored to explore Vision's anatomy ala Fantastic Voyage, they found resistance from a series of nanobots that released electrical charges to defend Vision from such invaders.
The Vision's Jewel Was Not Always the Mind Stone
In the MCU one of the Vision's chief qualities is the Mind Stone embedded in his forehead, tied in intrinsically with his origins and, unfortunately for the android, his death at Thanos' hands. In the comics, the Vision's origins have nothing to do with the Infinity Stones. Instead, the jewel on his head serves a completely different purpose -- it's a power source. The Vision fuels himself off solar energy the diamond in his head gathers up, allowing the synthezoid to bypass the need for sleep or food.
It also grants Vision an additional ability akin to heat vision. The android can release powerful blasts of stored thermal energy from the jewel, forming a white-hot beam of energy that can turn tanks to pools of useless slag. Given that the same energy fuels Vision himself, the ability comes with a limited reservoir of power.