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Real Name: David "Davey" Kalen

Identity/Class: Human mutate

Occupation: Environmental consultant

Group Membership: None

Affiliations: John Jameson, Dr. Ashley Kafka, Spider-Man (Peter Parker), Spider-Man (Ben Reilly), Edward Whelan (Vermin)

EnemiesMaggott (Japheth), Mr. Sanders, Spider-Man (Peter Parker), Spider-Man (Ben Reilly), Vulture (Adrian Toomes), X-Men (Captain Krakoa/Scott Summers, Marvel Girl/Jean Grey, Polaris/Lorna Dane, Rogue/Anna Marie Beaubier, Sunfire/Shiro Yoshida, Synch/Everett Thomas, Wolverine/Laura Kinney)

Known RelativesHenry "Hank" Kalen (brother, deceased)

Aliases: "Gukthing", "Mr. Trackin'-Mud-In-The-House"

Base of Operations: Greenlawn, New Jersey;
   formerly Ravencroft Asylum;
   formerly Hicksville, New York

First Appearance: Spectacular Spider-Man II#230 (January, 1996)

Powers/Abilities: D.K. is an amorphous super-strong being with the ability to decay anything he touches, including metal, wood, and human flesh - although he can handle materials without decaying them if he wishes to.  With some effort, he can transform back into his human form.


(Spectacular Spider-Man II#230 (fb)) - The Kalen brothers were hired by Sanders Chemical Corporation to inspect their facilities and bring them up to the new government regulations.  While Sanders' facilities mostly checked out clean, the Kalens extended their inspection to Sanders' off-site waste disposal facilities.  Finding an illegal dump of
toxic waste in Greenlawn, Long Island, the brothers planned to report it to the authorities - unaware that Sanders had booby-trapped it with explosives.  The subsequent explosion killed Hank and mutated David.

(Spectacular Spider-Man II#230 (fb) - BTS) - Pulling himself together over the course of a month, Kalen found that the explosion and the waste had mutated him into a sludge monster with the power to decompose matter.  He took another month to track down the "fixer" Sanders had hired to kill the Kalens, who confessed to the deed.  Kalen then turned his attention to Sanders. 

(Spectacular Spider-Man II#230) - Kalen attacked Sanders' New York City offices, looking for Sanders himself.  Unable to find him, Kalen escaped, despite the interference of Spider-Man (Ben Reilly).  Tracking Sanders to his chemical plant, Kalen melted the stairs and elevators, preventing security from interfering, and burst into Sanders' office.  Spider-Man had followed him, however, and briefly battled Kalen before being buried beneath a collapsing wall.  Kalen shifted back to his human form and confronted Sanders with the fixer's confession.  Before he could kill the businessman, however, Spider-Man tackled him out the window and webbed him up.  Reilly tried to persuade Kalen to let the courts handle Sanders, but Kalen told the hero that "there's nothing left of David Kalen anymore - except maybe his initials!"  Calling himself D.K., he escaped from Spider-Man's webbing and leapt upon the fleeing Sanders' car, melting it into goop.  Spider-Man grabbed Sanders, and stood between him and D.K., again telling him that Sanders wasn't worth killing.  This time, Kalen listened, and allowed the police to take Sanders away.  Kalen, back in human form, left with Ravencroft's John Jameson and Ed Whelan.

(Sensational Spider-Man I#16/2 (fb)) - Kalen signed himself into Ravencroft, and began treatment under the watch of Dr. Ashley Kafka.  Suffering from survivor's guilt, Kalen began to turn his powers inward, slowly rotting himself from the inside.  As he'd signed himself in, he was able to leave at any time, and, tired of being locked up and isolated, began to consider doing so.  Concerned, Kafka summoned Spider-Man, the only person Kalen truly trusted (Kafka, of course, was unaware that Ben Reilly had died months ago, and that the current Spider-Man, Peter Parker, had never even mat Kalen).

(Sensational Spider-Man I#16/2) - When Spider-Man and Kafka broached the subject of staying, Kalen went berserk, transforming into his monstrous form and bursting out of his cell.  Rampaging through the asylum, he aged three guards and melted two others before attacking Spider-Man.

(Sensational Spider-Man I#17/2) - D.K. lashed out at Spider-Man, who tried to talk him down.  Parker used his experience of losing a brother (Reilly) to calm the beast, who broke down upon seeing the corpses of the melted guards.  Kafka and a squad of Ravencroft guards brought Kalen back to his cell.

(Sensational Spider-Man I#18) - A few days later, Kalen melted his way out of Ravencroft and made his way to Central Park, where he began calling for Spider-Man.  When the web-slinger finally arrived, Kalen began to decay further, revealing that he'd only wanted to thank Spider-Man, for trying to help him.  Parker could only watch helplessly as D.K. malted into a puddle of sludge.  Before he had time to fully process what had happened, the currently-youthful (thanks to a machine called the Juvenator Machine, and...listen, it's a long story) Vulture swooped in to attack.  His spider-sense alerting him just in time, Spider-Man deflected the Vulture into the puddle.  Still possessing some spark of life, the puddle sucked the Vulture into its depths.  Spider-Man pulled the arch-criminal from Kalen's corpse, only to find that D.K.'s powers had re-aged him into an old man.


(X-Men Unlimited Infinity#35) - In Greenlawn, Long Island D.K. reemerged as a gigantic, mindless, green sludge monster. The X-Men fought the monstrous D.K. until Marvel Girl (Jean Grey) mercifully blew it apart. They thought D.K. was defeated when they sent in Maggott with Eany and Meany, but D.K.'s hand reformed for one last attack and killed Maggott and Meany.

   Locals had to take care of cleaning up D.K.'s remains after Maggott's death. They found Eany alive.

Comments: Created by Todd DeZago, Sal Buscema, and Jimmy Palmiotti.

And that's how the Vulture got old again, kids.

Awfully convenient that a guy with the initials 'D.K.' got decomposition powers, but it's probably more plausible than a guy named 'Octavius' getting tentacles fused to his spine.  And don't get me started on Basil Elks.

Cleaned up main image by Ron Fredricks.

Profile by Minor Irritant. Update by Markus Raymond (X-Men Unlimited).

D.K. has no known connections to



David's brother and business partner, Hank was killed in the explosion that mutated David.  His death prompted David to seek revenge on Mr. Sanders.

--Spectacular Spider-Man II#230





Sanders hired the Kalen brothers to inspect his chemical plant, but was unprepared for them to also inspect his illegal waste dump.  To prevent them from going public, he hired a "fixer" to booby-trap the dump with explosives.  Upon learning that David Kalen had survived, and had been transformed into a superhuman monster, Sanders increased security at his plant and hid out in it.  Evading Sanders' security, Kalen found Sanders, who was saved only due to the intervention of Spider-Man.  However, after being dissuaded from his vendetta, Kalen presented evidence that implicated Sanders in the murder of his brother, and the police took the industrialist away.

--Spectacular Spider-Man II#230



images: (without ads)
Spectacular Spider-Man II#230, p6, pan4 (main image)
Spectacular Spider-Man II#230, p16, pan5 (headshot)
Sensational Spider-Man I#18, p20, pan2 (liquefied)
X-Men Unlimited Infinity#35, pan1 (gigantic and green)
Spectacular Spider-Man II#230, p1, pan3 (Hank)
Spectacular Spider-Man II#230, p20, pan3 (Sanders)

Spectacular Spider-Man II#230 (January, 1996) - Todd DeZago (writer), Sal Buscema (penciler), Jimmy Palmiotti (inker), Eric Fein (editor)
Sensational Spider-Man I#16/2 (May, 1997) - Todd DeZago (writer), Rich Case (artist), Ralph Macchio (editor)
Sensational Spider-Man I#17/2 (June, 1997) - Todd DeZago (writer), Rich Case (artist), Ralph Macchio (editor)
Sensational Spider-Man I#18 (August, 1997) - Todd DeZago (writer), Jason Armstrong (penciler), Ron Boyd (inker), Ralph Macchio (editor)
X-Men Unlimited Infinity#35 (May 16th, 2022) - Alex Paknadel (writer), Julian Shaw (artist), Lauren Amaro (editor)

First Posted: 04/15/2007
Last updated: 11/19/2023

Any Additions/Corrections? please let me know.

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