Corrupted Gems

“	Even though we've already won the fight for Earth, we're still trying to keep it safe! There are battle-damaged Gems that are still around, and they're not like us. Something's really wrong with them. They're like horrible monsters. We have to poof their bodies away, and then keep their Gems inside of bubbles, so they can't form again and hurt anybody. Maybe someday I'll be able to heal what's wrong with them, but I'm not sure how. Mom couldn't fix them either. For now, we're keeping them safe inside the Temple.	”
—Steven, "Guide to the Crystal Gems"

Corrupted Gems, also known as Gem Monsters, are Gems who have become corrupted, assuming a monstrous form. One of the main objectives of the Crystal Gems (other than their protection of humanity) is to defeat and contain corrupted Gem monsters, and hopefully cure them.^[1]

Information

“	All those monster we fight used to be just like us! Right, Pearl. Yes. But they've become corrupted and broken.	”
—Amethyst and Pearl, "Ocean Gem"

Cause

Corrupted Gems used to be normal Gems prior to the events that unfolded at the end of the Rebellion. As a last ditch effort in the war for Earth, the Great Diamond Authority sent out a Corrupting Light which corrupted gems from both Homeworld and the Rebellion that had been left on Earth, most likely a means of ensuring the rebellion couldn't directly threaten Homeworld. In "Monster Reunion", the Centipeetle Mother described it as a "song" and remembering it seemed to be what triggered her to revert into her corrupted form.

It is revealed in "Earthlings" that secondhand corruption can occur to a non-corrupted Gem through fusion with a corrupted one as Jasper started corrupting after fusing with the Snow Monster and forming a semi-corrupted fusion.

Description

“	It's sort of like if MC Bear-Bear didn't tear the fabric of his arm, but the fabric of his mind.	”
—Garnet, "Monster Reunion"

The appearance of the Corrupted Gems vary greatly with different Gems. Although, in "Monster Reunion" multiple Centipeetle Mothers can be seen, hinting at the possibility that like Gems will take on the same corrupted forms. This is also supported in "Earthlings", in which several corrupted jaspers can be seen having taken wolf-like forms. As the bodies of Gems are mental projections, the bodies of corrupted Gems are a reflection of how damaged their minds are. Forms range from slightly humanoid, to monstrous, and in severe cases, not having a physical body.

Corruption sometimes also changes the physical appearance of a Gem's gemstone. As Centipeetle's gemstone had a curvy contour line that surrounded the circumference of the gem, and upon partial healing by Steven, the curvy contour line straightened. Jasper's gemstone, however, wasn't changed by her corruption.

Most corrupted Gems are hostile and dangerous, and behave similarly to wild animals. However, much like regular Gems, when their bodies are severely damaged, they explode into smoke, or "poof", leaving their gemstone behind. The gemstone can then be safely contained in a Gem bubble, preventing it from regenerating. Some corrupted Gems are imprisoned in objects (such as the Pyramid Temple's gemstone), which also prevents them from regenerating.^[2]

Corruption also seems to strip gems of some of their basic powers. They are unable to summon their weapons or use warp pads and other Gem structures, such as a door to a spaceship.

Healing

Garnet simply describes corruption as a tear in the mind of a Gem, rather than physical damage on their gemstone and as such is harder to heal than a cracked Gem. There is currently no known way for reversing the effects of corruption.

Steven's healing spit only partially and temporarily healed the Centipeetle Mother, but she reverted to her corrupted form shortly after. Garnet acknowledges this as a major step in trying to heal the Corrupted Gems even though Steven's attempt had failed, saying that it was the best that they've seen it work. She indicated that Rose Quartz was unable to heal the Corrupted Gems to the same extent her son, Steven, had done.

Known Corrupted Gems

TV series

Corrupted jasper fusion.png
Corrupted Jasper Fusion from "Earthlings"
Corrupted Jasper as of "Earthlings"

Comic book series

Steven Universe

Steven Universe: Too Cool for School

Mollusk

Steven Universe and the Crystal Gems

Trivia

When regenerating, the Centipeetle Mother briefly assumed a humanoid shape - presumably reflective of her original form.
It's unknown how many of the corrupted Gems are former Homeworld Gems and how many are former Crystal Gems.
- However, it can be assumed that the majority of corrupted gems were Crystal Gems, due to them not knowing about fleeing the earth.
Some corrupted Gems, such as the Worm Monster and the Centipeetle Mother, are shown to have an urge to eat food. The reasons for this are unknown, but it is possible that they do not gain sustenance from their gemstones like most other Gems do.
As shown by the Centipeetle Mother and her crew, it is possible for Corrupted Gems to be peaceful and even retain some aspects of their former personality, as Centi and her surviving crewmates retained their bond with one another, despite remaining corrupted.
As shown by the 2 Northern Gem Monsters from "Gem Hunt", Corrupted Gems are capable of feeling fear and their behavior indicates that Corrupted Gems may have a strong fight-or-flight instinct which may indicate that Corrupted Gems are not innately violent or hostile, but instead possess a mentality similar to a wild animal, attacking and /or fleeing from perceived threats. This may also explain the Centipeetle Mother's passive behavior towards Steven and the Crystal Gems after reuniting with crew despite being corrupted, as she no longer saw them as a threat as she originally did in "Gem Glow".
In "Monster Buddies" and "Crack the Whip", it is shown that Corrupted Gems can in a sense be tamed, though with varying results. In "Monster Buddies", Steven was able to befriend and bonded with the regenerated Centipeetle Mother. In "Crack the Whip", Jasper managed to tame the two Corrupted Gems she captured in "Gem Hunt", through the use of intimidation and physical domination. While seemingly effective at first, due to her method's cruelty, the two gems lack any real loyalty to Jasper as they followed her mainly out of fear of her and would abandon her if given the chance as show in both "Crack the Whip" and "Earthlings".
Unreleased corrupted Gems can be seen on Guy Davis' Tumblr, such as the Stinger, the Fist Chest, and the Shell Back.^[5]
Garnet's description of the difference between cracked and corrupted gems in "Monster Reunion" is spot on. Where gem cracking can be represented by significant physical damage, gem corruption could be representative of mental damage. The etymology of "schizophrenia" is "the splitting (or tearing or fracturing) of the mind"^[6], a word that for years was used to broadly describe just about any mental illness until the 1970s when significant changes to how mental disorders are diagnosed were made. Schizophrenia does not imply that a person has multiple personalities. That diagnosis belongs to Multiple Personality Disorder, which is a completely different diagnosis and is often not related to schizophrenia. The most common mental disorders are anxiety disorders (including PTSD) and depression.^[7] How the series will handle the issue of gem corruption is still to be determined, but it is quite clear that it will be the topic of future episodes following "Crack The Whip".
Being poofed or put into an object can save a gem from being corrupted by the Corrupting Light. It is unknown whether being trapped in an object or being poofed in general is what saved Lapis.
It is revealed in "Earthlings" that corrupted Gems are capable of fusing with regular Gems.
- However, this will cause the uncorrupted Gem (as shown by Jasper's corruption) to become corrupted once the fusion is ended. It is currently unknown if Corrupted Gems are capable of fusing with other Corrupted Gems.
  - It should be noted however, that Jasper's corruption may have been amplified by her rage towards Rose Quartz, coupled with the fact that she had once again lost to a Crystal Gem fusion and had been abandoned by her fusion partner.