Just posting this here because once images are stored on CV's server, they're easier to transfer to other places; plus I cannot stand photobucket's interface. Also J'onn is vastly underrated so it can't hurt to have it here. Enjoy.
Justice League of America #256: J'onn momentarily connects with the mind of Adam, a cultist who attained vast reality warping powers by stealing the genetic imprint of the Homo magi and connecting with an entity called the Godhead (described as being the embodiment of all that was, is, and will be).
Justice League of America #257: Bonds Adam's mind to his own to keep him calm and stable and ensure the safety of Zatanna and Gypsy as they shrink into Adam's consciousness to fix him. The fourth scan is an example of how powerful Adam was: he could warp reality, alter time and destroy/recreate worlds just by getting upset.
Justice League #6: Fistfight with Captain Marvel when Batson was possessed by a sorcerer called the Gray Man. Note that the only power he uses here is brute strength. The fight probably would have been a lot easier if some phasing and shape-shifting had been tossed in, but writers rarely got creative with J'onn's powers back then. At any rate, Batson gets the advantage near the end until the possession ends, and then J'onn gets back up and knocks him out with a hard uppercut. It's possible and perhaps even logical to attribute the advantage Marvel acquired to the fact that J'onn was fighting two battles at once, not just one: while he was physically tussling with Billy he was simultaneously fighting (and winning) a psychic battle to free Marvel and Dr. Fate from the Gray Man's control. The last scan is a visual of how the Gray Man could slowly take control of the entire planet to put the feat into perspective. Managing to take control of Dr. Fate requires considerable psychic power as well.
Martian Manhunter #4: This one is kinda weird; it's revealed that J'onn's mind was subconsciously keeping the souls of the entire Martian race (all of them telepaths) stranded on the living plane and unable to move on to the afterlife. He finally lets go and the Martian god H'ronmeer takes them away.
Cosmic Odyssey #2: Connecting with the mind of the New God Metron.
Justice League of America #40: J'onn's one and only win over Despero, admittedly via a plot device Martian power that was never seen again. J'onn even states that it's a one-time thing and can't be done again.
Justice League of America #61: The Weaponmaster fights and swiftly defeats several Leaguers (Maxima, Guy Gardner, Booster Gold, Blue Beetle, Superman, Fire and Ice) until J'onn appears in his Bloodwynd form. Lacking a proper response for his abilities, the Weaponmaster flees.
Slight digression to elaborate on J'onn's phase as Bloodwynd. The Blood Gem had attached itself to J'onn and tricked him into thinking he was Bloodwynd, so he changed his appearance into that of Bloodwynd while the real Bloodwynd was trapped inside the Gem. Accordingly, J'onn in his Bloodwynd phase would attribute most of his powers to those of Bloodwynd (for example, while using his natural Martian strength he would say "Spirits of the dead, give me strength!"). Once separated from Bloodwynd, J'onn clarified that most, if not all, of the powers and feats Bloodwynd displayed were just his own natural Martian abilities with some pseudo-mystic language and flowery descriptions attached to them.
Justice League of America #64: J'onn/Bloodwynd breaks through Starbreaker's (the dude who can consume the energy of suns like J'onn consumes cookies) psychic defenses and probes his mind to uncover his history until the latter manages to eject him with some effort.
Justice League of America #64: In the same issue, while absorbing the League's energies, Starbreaker states that J'onn's power exceeds Superman's. That places him only one rank below Batman, so not bad, all things considered.
As for the credibility of the source, Starbreaker can eat goddamn suns, so I'd say he's familiar with power.
Justice League Task Force #27: J'onn's Martian vision can damage the Ray (who is intangible in his energy form) by scattering his atoms where it strikes.
Justice League Task Force #28: Hands Triumph the pink slip, the old fashioned way.
What, old school employers didn't beat their employee like a dog before firing him/her? Madness.
To put this into perspective, here are some of the things Triumph has done: knocking Maxima away with one punch and later taking on several members of the Justice League and winning; Superman needed help from Steel to finally beat him.
He could also draw upon the power of the entire planet's electromagnetic sphere, generate EMP's, manipulate technology and energy signals and amp his strength to the point where he could duke it out with folks like Kal-El. His powerset was essentially a Superman/Magneto hybrid with a few alterations here and there to reflect the electromagnetic origin of his abilities.
Justice League Task Force #31: Gypsy remarks that J'onn could kick Superman's butt. She's not really an authority on what it means to be powerful; nor is her perspective unbiased since she and J'onn were like peas in a pod -- but I cherish the times when DC writers make these kinds of statements, so bear with me here since there are going to be more of them in this thread.
Justice League Task Force #32: Ejected out of a spaceship moving at eight times the speed of light (stated as such on the first scan), J'onn flies after it and after not being able to bridge the gap, he instead pulls himself up to the ship with a telekinetic grip and then phases through the back. Effectively reacting to tag and take action to something moving at eight times the speed of light.
Justice League Task Force #37: Triumph starts a fight and Maxima, Bronze Tiger, Gypsy, Blue Beetle and a few others join in. J'onn stops them with one telepathic word. Notable because Maxima is among them, and she's among DC's more famous telepaths when she's not trying to get knocked up by Superman.
Martian Manhunter Special #1: Stated to have traveled across innumerable light years, which would necessitate FTL flight.
JLA: Secret Files #1: Defuses a twister with his speed and later creates a substitute for uranium miners in his spare time. Because he can do stuff like that.
JLA: A Midsummer's Nightmare #2: Telepathically scouring the minds of everyone on Earth; nearly all of them had superpowers courtesy of Dr. Destiny's reality warping.
JLA: A Midsummer's Nightmare #3: Phasing through a force-field that tanked hits from Superman and Green Lantern.
Green Lantern #87: Telepathically taking control of a spaceship three times the size of Manhattan via its dual mechanical/organic interface and diverting its course away from Earth and towards Mogo.
Wonder Woman #125: Shapeshifts into an exact duplicate of Wonder Woman, phases into her body such that their cells were perfectly aligned, and then converting a massive jolt of electromagnetic energy from Bluperman into psychic energy.
JLA #11: Shapeshifts his own brain into a particular shape in order to make himself as insane as the Joker.
JLA #15: Forces the Joker to become sane for a while. Joker at the time was in possession of the Worlogog, an object that can warp time and space on a massive scale (Hourman has used it to freeze an entire universe still, and Extant has repeatedly used it to make reality his b!tch) and was using it to create a ten thousand mile earthquake on the Earth from the Moon. J'onn stepped in and cut off his thoughts from the Worlogog, allowing Flash to snatch it out of his hands.
JLA #20: Taking action at speeds faster than thought alongside Superman, Flash and Hippolyta. They were moving so fast Orion, Barda, Steel and Kyle Rayner were standing still, although Hippolyta needed a speed boost from Wally since she's not as fast as her daughter.
JLA #21: J'onn was the only member of the League who could shield his mind from the telepathic En'Tarans, who enslaved the rest of the League as well as the entire population of the planet Rann.
JLA #23: Earth is attacked by several Star Conquerors, each one capable of putting an entire continent the size of North America to sleep. J'onn protects Aquaman when one of them starts to invade his mind, and later broadcasts a counter-frequency that forces all the Star Conquerors to leave Earth.
DC One Million #2: Containing the spread of the Hourman virus inside his body so that it would not alter his behavior. The Hourman virus was a disease potent enough to debilitate the mindsets of people like the Justice Legion (including Superman One Million, Aquaman One Million and Wonder Woman One Million), Firestorm and the Metal Men.
Martian Manhunter #0: Switches off his telepathy to become immune to a wall of fire, and then fights his brother Malefic. He eventually defeats him (although he considers it a loss since he wanted to die).
Examples of what Malefic is capable of: beating up Aquaman, Steel and Huntress without even trying to really hurt them (he was pretending to be J'onn to defame him in the eyes of the League), decking a running Flash while invisible, one-shotting Barda (while pretending to be Superman) and dodging Orion's blasts while remarking that the New God was too slow to hit him, beating up Plastic Man and taking his form.
Martian Manhunter #2: Absorbs mass and metal debris to grow over a hundred feet tall with an armored coating.
Martian Manhunter #3: Uses telepathy to force Bette Noir, a psychic vampire who exists in an energy form, back into her deformed body.
Martian Manhunter #4: Scans the minds of everyone on Earth to find the person who killed his partner on the police force.
JLA: Year One #2: Schooling Clayface on proper shape-shifting.
JLA: Year One #7: His best Tony Stark impression.
JLA: Year One #8: Quickly escaping from a construct-cage created by Hal Jordan, presumably via invisibility + intangibility.
Martian Manhunter #7: Forced into a confrontation with the JLA by his evil brother Malefic, J'onn takes hits from Superman, Barda, Wonder Woman and Orion one after the other and not only does none of that even slow him down, he is able to combine his shape-shifting with his strength to manhandle Wonder Woman, Orion and Barda simultaneously as well as prevent Aquaman from being able to harm him before leaving to make sense of the whole situation.
Martian Manhunter #8: Regenerates his entire body from a severed arm that he'd placed a backup consciousness in.
Yes, he can do stuff like that!
JLA Annual #3: One of Grodd's machines turns the JLA into gorillas (please don't ask) and J'onn is the only one who can maintain his personality and not go completely feral. The rest of the League (Superman, Wonder Woman, Flash and Aquaman) can't, so J'onn gives them a telepathic bitch-slap to remind them of who they are and then they go back to the Watchtower.
JLA Annual #3: Later on, they regress back to being apes mentally and Superman, Flash and Aquaman try to court Wonder Woman, so it falls on J'onn to give them yet another telepathic bitch-slap. The slave of duty and all that.
Martian Manhunter Annual #2: Gorilla Grodd builds a device that amps his telepathic powers to the point where he's above J'onn in sheer psychic ability; but the Martian still beats him anyway by literally talking Grodd into giving himself brain damage.
JLA #35: Enters the Spectre's mind and forces him onto the astral plane, pulling the rest of the JLA along for the ride.
Martian Manhunter #13: Phases through a White Martian's Martian vision beams.
JLA #40: Breaks through Mageddon's psychic defenses to reach Superman.
JLA #41: Breaking through Mageddon's telepathic defenses again to connect Batman to Superman.
This is one of J'onn's more impressive telepathy feats because Mageddon was an extremely powerful telepath. To put the feat of getting past its psychic defenses into perspective, these are some of the things Mageddon has done: practically destroying Hector Hammond's (a planetary-scale telepath) mind, causing two wars to break out in the space of five minutes, forcing an entire planet full of the Old Gods (a single Old God could reality warp everyone on Earth to give them powers) to kill each other, driving everyone on Earth out of their minds with rage and fear and making them go to war, and with the exception of that last feat, all the others were done while Mageddon was light years away from its target.
Hourman #16: Joker uses Kanjar-Ro's sceptre to make J'onn and Flash go crazy and then makes them fight. They have a high-speed slugfest where J'onn goes blow-for-blow with Barry. Going blow-for-blow with a Flash in a state like that is a speed feat that very, very few have ever been able to replicate; and all of those few are either high-level speedsters themselves or Hunter Zolomon.
JLA: Superpower: Shutting down Antaes' power suit by phasing through it.
Martian Manhunter #19: Defeats New God and master assassin Kanto in armed combat.
Martian Manhunter #20: Telepathically coaxing information out of Superman's Kryptonian rocket.
Martian Manhunter #23: Scanning the mind of Jim Corrigan and briefly viewing the true face of the Spectre.
JLA #50: Scanning the mind of Dr. Destiny. J'onn initially thought that he was being blocked by Destiny since he could only see dream-images, but later realized that he had actually succeeded in getting past Destiny's shields and reading his mind; the dream-images were caused by Destiny's dream-self swapping places with his real self.
Destiny is an uber-powerful reality warper, which makes scanning his mind another one of J'onn's high-end telepathy feats. To put the feat into perspective, these are some of the things Destiny has done: plucking nightmares out of the minds of several people (including Riddler, Two-Face and Starman) and turning them into reality, driving everyone on Earth mad with his thoughts, warping the entire planet to create a new world where characters were mash-ups, creating multiple alternate realities from dreams.
JLA #51: Another high-end telepathic feat: inducing a telepathic hallucination in the mind of Joseph Stinton, a man who had been made borderline-omnipotent by sixth dimensional beings to the point where he could turn his every whim into reality, and holding it long enough for Flash and Superman to conduct brain surgery on him to cut off his access to his powers.
Stinton's sole feat is BFR'ing Superman to Saturn in the blink of an eye and he was stated to be able to remake the world with a thought; but there are several other feats from the 6D beings that illustrate the scale of the reality warping involved: turning an entire city into chocolate, resurrecting Metamorpho, randomly turning the subconscious desires of people all over the world into reality, blinding everyone in an entire city, turning Wonder Woman into clay.
JLA #53-54: The same nigh-omnipotent 6D beings unleash a blast that KO's Superman, Wonder Woman, Flash, Aquaman et al immediately, but J'onn manages to be the last one standing and remain conscious long enough to download all the details of the confrontation into the minds of the alternate League.
Martian Manhunter #24: Shape-shifts into the Hulk!
JLA #55: Nine White Martians who had absorbed the brain matter of human psychics to amplify their telepathy to the point where they could use it across light years attack J'onn. They subdue him physically but even their combined efforts cannot break through his mental shields.
JLA #57: Killing two White Martians by phasing through them and attacking their hearts. While these two were nameless, standard displays of power from White Martians should disabuse any notion that they were just fodder --- there's a separate section below the respect section called Generic Martian Capabilities that illustrates what even nameless Martians can do.
JLA #57: Using his speed to blitz several towers on every continent and take out numerous White Martians in the space of a few seconds. These same Martians easily stomped every hero on Earth and were blitzing Wonder Woman and Green Lantern ---- but all of that is for the Generic Martian Capabilities section.
JLA #58: Mind-wiping the entire Justice League.
Martian Manhunter #35: Defeating his brother Malefic in a telepathic battle.
Action Comics #774: Pulls Superman onto the astral plane and into his mind with a single thought and holds a conversation within a sixth of a second.
JLA #64: Telepathically keeping the god Vishnu asleep so that he wouldn't wake up and end the universe.
In this story, the beliefs of people all over the world were becoming reality, and it was a universe-wide event. Aside from the other two events mentioned in the above scan (transforming the moon into green cheese and reigniting the American Civil War), there are several other events caused by the reality-warping effect that lend credence to the idea that Vishnu could have ended the world/universe if he had woken up: fundamental tenets of mathematics were rewritten, the Earth became the center of the universe, the Earth became flat, a statement from Wonder Woman that the universe was nearly unraveled.
Effectively, J'onn's telepathy saved the world and/or universe.
JLA #75: Pulls the Earth along with Superman and Wonder Woman.
JLA #83: The beginning of J'onn's Fernus period, where he lost his fear of fire and thus all his restrictions on his own power. The downside is that he went insane and manifested a new personality called Fernus and became a Martian murder machine, but more on that later. The first thing he did was force everyone in Arkham Asylum, including the Joker, to become sane.
JLA #83: The second thing he did was deliver a brutal invisible beatdown to Firestorm, culminating in him telepathically cutting off Ronnie's access to the Firestorm matrix, leaving him powerless and dying on the moon.
JLA #84: Shape-shifting into a tree and scanning every mind on Earth.
JLA #84-85: J'onn as Fernus vs the Justice League, Round 1: Incapacitating Superman by phasing him into the JLA Roundtable, tearing out John Stewart's guts, one-shotting Flash and then just generally slapping around the rest of the League until Major Disaster brought a comet crashing down into the Watchtower to buy some time for the League to run away. And all of this was done while J'onn/Fernus was, according to Batman, holding back.
JLA #86: Superman calls J'onn the most powerful being on the face of the Earth, and says there's no one he'd be more afraid to face in open combat.
JLA #86: Slaughters every White Martian in the Phantom Zone. These were the same White Martians who stomped every single hero on the planet back in Terror Incognita. Fernus may have had an unfair advantage since he was on fire, but these same White Martians had developed techniques to get past their fire weakness via speed and stealth (more on that in the Generic Martian Capabilities section) and none of that helped them against Fernus.
JLA #87: Fernus vs the Justice League, Round 2. This time he doesn't even bother getting physical --- he just wastes the League's minds. The League is saved by John Stewart showing up with a special helmet designed by Ganthet to give him telepathic immunity for 60 seconds, buying enough time for the League to run away (again).
JLA #88-89: Fernus vs the Justice League, Round 3: Fernus grows to a hundred feet tall and defeats the entire League again --- including Superman, Wonder Woman and John Stewart --- and then Plastic Man shows up and fights him. He had some weird plot power about how his inorganic brain was untouchable by telepathy, which doesn't even make sense since J'onn's telepathy has worked on him before and so has the telepathy of nameless White Martians, but whatever. Plastic Man + the rest of the League combined still can't bring down Fernus, but when Fernus attacks Scorch and sends her into a coma, J'onn summons his will and reclaims control of his mind and body from Fernus, finally destroying him right down to the molecular level with his Martian Vision.
Firestorm #6: Planting a psychic tracer in Firestorm's mind to track his location anywhere in the world.
Justice Leagues #5: Reading Orion's mind.
Infinite Crisis #6: Phasing through Superboy-Prime's heat vision and smacking him away. This was a few pages after Prime laughed off punches from Black Adam.
Infinite Crisis #7: Defeating Captain Cold and Mirror Master (off-panel), reading Superboy-Prime's mind and relaying his intentions to every hero on Earth.
JLA Classified #3: While severely weakened from being inside a volcano, J'onn reforms his entire body from a green smear on the wall.
World War III #4: Scanning minds all over the world to see how people in different places are reacting to Black Adam's rampage. One of the minds he locks onto is the Spectre's.
World War III #3: Casting his mind out over the globe to find Black Adam, locating him, and then occupying a back space in Raven's mind without her knowledge to view the battle.
Martian Manhunter #4: Moving fast enough to snatch away a woman in a blur.
Martian Manhunter #5: Bullet-timing reflexes. Not really impressive for characters of this level (unless you're Thor, in which case.....hallelujah) but still: bullet-timing.
Martian Manhunter #7: Blowing up a mansion via Martian Vision.
JLA Classified #12: Talks smack to President Luthor.
JLA Classified #19: Shrinking himself down to the size of a blood vessel and entering a man's Starro-infested bloodstream.
JLA Classified #21: Prevents the Starro strain from taking control of his mind by shifting his brain's position through his body.
JLA Classified #44: Knocking out Weather Wizard and getting him into police custody so quickly that Wally West himself remarked that it was fast.
JLA Classified #45-46: A piece of Malefic's soul stored inside J'onn's mind from their childhood takes control of his mind and body. Malefic uses J'onn's powers to fight the League, knocking out Wonder Woman (off-panel), swinging her body through the air like a club to beat Superman with, matching Kal-El's heat vision, shutting down Flash's mind, and shape-shifting out of Wonder Woman's lasso before using his telepathy to dominate the entire League at once.
I like that Batman built a device to block telepathy like that's half the battle won or something.
JLA Classified #46: Overpowering Malefic and freeing the JLA from his control by cutting the piece of his brother's soul out of his mind, sending him into a coma that the League eventually brought him out of with Zatanna's help.
JLA Classified #52: While in a comatose state, J'onn shifts his consciousness into John Stewart's mind to possess his body and then telepathically scans entire dimensions to locate a time-displaced Flash.
Madame Xanadu #21: Travels a distance with his speed faster than Madame Xanadu could teleport to the location. He was using his John Jones alias in this story.
Madame Xanadu #23: Using his speed to save Madame Xanadu from a car.
Outsiders: Five Of A Kind: Thunder & Martian Manhunter: Thunder says her father once told her J'onn was more powerful than Superman.
Like I said, I like stuff like this. Sue me.
Outsiders: Five Of A Kind: Thunder & Martian Manhunter: After Kyle Rayner uses his godlike Ion powers to shatter Grayven's mind, J'onn is the one who repairs the damage and stitches the New God's psyche back together again.
Final Crisis: Requiem: As preparation for Apokolips' invasion of Earth, Darkseid's soldier and living embodiment of the Anti-Life Equation Libra forms a new Secret Society, and the first thing they do is capture J'onn by shooting him with over three hundred pyro-tranq darts designed by Dr. Sivana, but even in that weakened state and even after being stabbed through the chest by a weapon Darkseid himself gifted Libra when he empowered him, J'onn is still capable of forcing the entire Society (Luthor, Effigy, Grodd, Sivana, Talia al Ghul, Ocean Master, Dr. Light and Vandal Savage) into a telepathic nightmare until Libra recovers from the hit that he received and stabs J'onn again to disrupt the illusion.
Also notable is the fact that Dr. Light (who has brought down Superman with one light blast, curbstomped Kyle Rayner, and fought an army of Titans by himself) says he wouldn't stand a chance against a fully conscious J'onn, and Libra (who has defeated Superman, Green Lantern and Flash in the past, and after his empowerment by Darkseid was able to block the power of the Crispus Allen Spectre) says he'd hate to have to take on J'onn in a fair fight.
Final Crisis: Requiem: While practically dead from all the damage received, J'onn manages to download his entire life history into the minds of Superman, Batman, Black Canary, Green Lantern and Gypsy as his final act, to make them the custodians of the Martian heritage as his final act.
Fast forward, everybody mourns, Final Crisis comes and goes, Blackest Night comes along and Nekron just ruins everybody's day, but at the end of it the Entity resurrects several dead people, one of whom just happens to be J'onn, so everything worked out better than expected.
Brightest Day #21: Fights D'Kay D'Razz, an insane Green Martian, and defeats her by summoning the thoughts of everyone on Earth (while standing on Mars) and blasting her with them. Then he kills her by flying her into the Sun, while getting there in under 8 minutes (unless for some reason he was having the slowest conversation in the history of communication) thus making it FTL travel.
Examples of D'Kay's telepathic power: she could receive the thoughts of billions of minds at once without even meaning to, and easily defeat Miss Martian in a psi-battle.
Brightest Day #24: An example of finesse in his intangibility: removing an inoperable wound from the brain of Melissa Erdel without harming her in any way.
Stormwatch #1: An angry Apollo punches J'onn in the face, and not only does nothing happen, but Apollo actually falls down as a result.
Stormwatch #1-2: This is mainly here to refute the claims that Midnighter one-shotted J'onn; he did no such thing. J'onn was faking.
Legion Lost #6: Fights some Legion people. Tanks anti-matter blasts from Wildfire, shapeshifts into a dragon thing, etc etc.
Green Lantern Corps #4: Telepathically manipulates Guy Gardner's emotions and then probes the mind of a Keeper, a being made of pure willpower.
Green Lantern Corps #5: Links the minds of nine Lanterns together and then erases all memory of his visit from their heads.
Justice League #8: Fights the entire League --- Superman, Batman, Wonder Woman, Flash, Green Lantern, Cyborg and Aquaman --- at once and holds his own, and later reads their thoughts while they're on the moon and he's on Earth.
There aren't a lot of details about this fight yet, but there are some key points that can be inferred at this stage. As to whether the League was holding back or giving it their all, there aren't any clues; but it is logical to assume that at least one member (Wonder Woman) was not holding back, since in Wonder Woman #0, War taught Diana to never raise a sword against a man unless she intended to end his life with it. That is consistent with how she's portrayed in the main JL series. For example, she only pulled out the sword against the Talons after Superman told her they were already dead to begin with. It's a weapon she uses when she's looking to kill.
This fight is going to be elaborated upon in the new Justice League of America series written by Geoff Johns, the same guy who wrote this issue of Justice League, so details will emerge from there ----- although I'd be surprised if the Martian didn't come out on top. Johns loves J'onzz and usually writes him like a boss, so there's that.
Stormwatch #12: Erasing all memory of his existence from Jenny Quantum's mind. Jenny is a reality warper who can generate logic bombs that unravel whole dimensions, making her the most powerful person J'onn's telepathy has affected in present continuity. She also blasts J'onn to no effect before her memories are erased.
I think that's all I got so far.
Generic Martian Capabilities
This section is here mainly because a few of J'onn's feats above are against nameless Martians, and it seems strange to try and dismiss those opponents as fodder just because they're nameless since so many of those nameless Martians have very strong showings against established heroes; showings that establish the average Martian as being significantly more powerful than the average Kryptonian, Daxamite, Green Lantern or New God.
Since this is, as mentioned, a display of generic Martian capabilities, Miss Martian's feats haven't been included here since she's a more or less established hero. Not that it really matters, there are nameless Martians with better showings than her considering her best showing is stalemating Supergirl. All of these feats below are feats of White Martians, since with the exceptions of Malefic and D'Kay (whose feats are already included in the main section) J'onn was the only Green Martian.
Without further ado....
JLA #2: A White Martian named Tronix one-shots Wonder Woman with her Martian Vision.
JLA #2: A White Martian named Primaid moves so fast that she blitzes Superman before he can react even though he saw her coming from over 200 miles away.
JLA #2: The White Martian leader, Protex, incapacitates Superman with a telepathic trick that makes his mind think there's Kryptonite in front of him.
JLA #3: Flash manages to be the only member of the League who beats the White Martian sent after him by the Hyperclan ---- but this is still a good speed showing for Zum given that there are only a handful of speedsters fast enough to make Wally West sweat.
JLA #3: Two White Martians named Armek and Zenturion beat Flash and Green Lantern in an off-panel fight.
JLA #33: A single White Martian takes on Orion, Steel, Green Lantern, Big Barda and Plastic Man all at the same time and more or less holds his own until Orion has a Crowning Moment of Badassery where he sets himself on fire to fight the Martian.
JLA #55-56: Two White Martians mind-control half a million people and make them march towards certain death in the form of a nuclear explosion. Then they mind-control Kyle Rayner and make him fire a lethal blast at Wonder Woman. Flash races through the crowd and places the Martians in the path of the blast in a picosecond. They tank it and then phase out of Wonder Woman's lasso when she ties them up in it.
JLA #57: White Martians blitz Superman and Kyle Rayner to defeat them.
JLA #57: Two White Martians turn invisible and clothesline a running Flash.
JLA #57: A White Martian scans Plastic Man's mind to uncover his real identity and then slices him in half with Martian Vision.
JLA #57: White Martians blitz Green Lantern, Wonder Woman and an already injured Flash.
JLA #57: Protex steals Phantom Zone intel from Superman's open book of a head.
JLA #58: The White Martians fight and defeat basically every hero on Earth worth anything.
JLA #58: Alan Scott and Superboy try to exploit the Martian weakness to fire, but the White Martians use their speed and stealth to avoid that and defeat them anyway.
JLA #58: The White Martians fly from the Earth to the moon in less time than it takes Superman to make a speech.
That really is all I've got so far. Cheers.