Light Is Not Good/Comic Books

In WITCH (the original comics from which the animated series were based on), Arkaam the White Queen turns out to be a despotic bitch. Her magical artifacts are also defenitely light or fire based. An earlier villain, Tridart, a servant of Nerissa, was angel themed and white, but his powers were ice based.
- Kandrakar keeps a prison, the Tower of Mists, whose inmates are complete monsters. Their cells are tailor-made to mind rape them into submission with Irony (the magic stealer Phobos was closed in a magic-absorbing cell, Cedric, the in-universe Prince of Lies, had been imprisoned in a cell made of lies, et cetera). Apparently it's so bad that Phobos preferred a Fate Worse Than Death to return in there...
Nemesis who is a villain in a pure white costume.
In The Children's Crusade, Doctor Doom becomes a white-robed man with holy magic after absorbing the Earth's life energy from the Scarlet Witch.
The Dawn of the White Hand were a brief lived foe organisation to the X-Men. It was based on Japan, where the colour white is still associated with death.
- While currently heroic, Northstar has had a history of face heel turns, most notably during his time under HYDRA.
The White Martians are an Exclusively Evil race with pure white skin
The Angelus from the The Darkness/Witchblade universe. Unquestionably a force of light and law. It just so happens that the Angelus is a completely sociopathic entity that believes the world should be run by her light and her laws.
In an old issue of Superman, the Man of Steel confronted seeming angels, standing guard before the gates of Hell. After he worked out the truth and threw off their illusions, he asked the Space Policeman who took them away why they hadn't changed. The cop calmly told him that they really did look like that.
While Karolina Dean of Runaways is heroic; her parents, who shared her light powers, were supervillains.
The comic book version of Dr. Light warrants his own entry, given that on top of his villainy, the Identity Crisis miniseries also retroactively made him a serial rapist. This is the male Dr. Light (who appears in Teen Titans). DC actually has two. The female Dr. Light (who appears in Justice League Unlimited) is at worst a case of Good Is Not Nice.).
The DCU also has Solaris, the evil AI sun from the future.
The Marvel Universe has Lightmaster, a recurring foe of Spider-Man. The Living Laser is another light-themed villain.
And several comic companies, including the Big Two, have used stories of Angels turned overzealous.
BPRD story arc The Dead: the villain used a salvaged version of the Spear of Destiny to open a gateway to Heaven and released one of the Six-Winged Seraphim. Whilst it does match every qualifier of the Seraphim, it's not going to be in the murals at your local Church.
Air Walker, the angel themed herald/former herald of Galactus. He wasn't that good in a lot of his showings.
- Overlaps with Cybernetics Eat Your Soul: most of the times Air Walker appears, he's a robotic rebuild of the original, who was a member of the Nova Corps and a decent person before he signed on as Galactus's herald.
- Stardust, a being of pure (and bright blue/white) energy and Galactus's latest herald, is also quite Ax Crazy, insisting on slaughtering the entire population of any world Galactus consumes, even though Galactus himself has no interest in killing the people (though he has no particular interest in not killing them either).
Inverted and then played straight in Cerebus. Prior to his religious conversion, Sim depicted a creation myth in which the female Light was essentially raped by the male Void in which it resided, causing the Light to completely shatter and form the physical universe. After his conversion, the male void became God and the female Light became YHWH, God's Adversary. Cerebus is physically dragged into the Light after his death in the last issue, screaming for God to save him.
Green Lantern plays with this a little. Certain "colors" in the "Emotional Spectrum" are more evil than others. Red (rage), orange (greed), and yellow (fear) are mostly evil, but green (willpower), blue (hope), indigo (compassion), and violet (love) are mostly good. However, black is so evil it makes all lights look good by comparison, even the evil ones.
- In technicality, all colours are neutral, and "good corps" had their own morally inconvenient moments. The Star Saphires, for example, have a history of Love Makes You Crazy and the Guardians have caused many problems. Blue Lanterns are all good, but their light is very limited in terms of power, so they are often incapable of doing much, while the Indigo Tribe has mercy killed many people, and it is composed of sociopaths brainwashed by the Indigo light anyway.
- We can safely add the White Light entity to the list now, thanks to the amount of morally ambiguous acts it has made, such as killing a couple because they love each other and would not obey to its command and separate.
- Blue Lanterns will show you visions of hope, but its really just anything that will make you feel hope whether it has any truth to it or not (though presumably plausible visions are more effective than implausible ones).
In the first issue of the Mice Templar comics, (nocturnal) mouse children are told scary stories about the "world of day".
Snowflame, a one-shot villain from New Guardians, is perhaps the strangest example of this trope. By smoking cocaine (really) he uses what appears to be light manipulation/white flames, and has a white motif, notably his hair. He is also an Ensemble Darkhorse, by the way, thanks to the sheer strangeness of using a drug as fuel for his powers.
The sun like creatures known as "thristies" in Marvel's Kool Aid comic.
In one of Alan Moore's issues of Swamp Thing, John Constantine wonders why everyone thinks of angels as comforting, confessing to the reader that they scare the shit out of him. They do indeed seem to be not so much unalloyed good as merely preferable to the demons.
- Actually, in the more cynical DC books, the metaphysical battle has nothing to do with Good versus Evil -- it involves Order (angels, Lords of Order) versus Chaos (demons, Lords of Chaos), with neither side paying any attention to good or evil as humans understand those terms. This has been a major motivation for The Phantom Stranger and Deadman in their choice to side with humans instead of The Omniscient Council of Vagueness of the week.
  - This has been standard DC metaphysics throughout the entire line ever since the Kali Yuga plot a decade ago.
Rainbow Raider from the Flash's Rogues Gallery. He's kind of dead now, though.
In contrast to Batman, The Joker. He dresses in bright colours, his skin is bleach white and has a sunny disposition. He's also the Trope Codifier for Monster Clown, and the most iconic supervillain there is.