Marriage Toxin (Monster Transformation)

Our thanks to T-Ace Juice on our Discord server for recommending this scene from episode 12. There's a partial TF at the start, and a full one at 2:30:

Man-Thing (Plant Monster Transformation and Pig Reversion)

Our thanks to the anonymous commenter who recommend the 2017 Man-Thing comic miniseries, written by R.L. Stine. From issue #1:

The cover of issue #2:

From issue #3, a trippy sequence involving a pig-to-human reversion: 

X-Men '97 (Alien and Monster Transformations)

Thanks to Andréssaurio Rex for finding these scenes. In episode five of season two ("Weapon X, Lies, and DVDs") the X-Men fight the Brood, aliens who can infect and transform humans.

In this scene, a scientist is possessed and transforms:

 

Later on the X-Men watch a DVD showing another brood metamorphosis:

 

Also, in the previous episode ("Rise of Apocalypse" Part 2) there's a short scene of a mutant turning into the monster villain Apocalypse:

 

Batman: Caped Crusader (Monster Transformation and Muscle Growth)

The first season of episode two ("Brute Force") shows mobster Mark Desmond being injected with a serum, created by Dr. Hugo Strange, which turns him into a hulking monster. The episode and the design of the monster reference the 1940 story "The Giants of Hugo Strange," from Batman #1, while the name Mark Desmond references the 1960s villain the Blockbuster, who also turned into a super-strong giant.

This clip includes a reversion at 01:20.  

Blood Reign: Curse Of the Yoma (Spider and Monster Transformations)

Thanks again to Andréssaurio Rex for suggesting this OVA from 1998, which has two transformation scenes. The video is cued to the first, involving a spider-monster. For the second, of a demon combining with his horse to create a blob that turns a wolf-centaur (!), go to 01:14:48.

 

Saros (Alien/Monster Transformation)

Thanks to Mr.TF on our Discord channel for recommending these cut-scene endings to the video game Saros. The "bad ending" is a gnarly monster/alien/demon metamorphosis:

 

 

 

The "good" ending is a partial curtailed TF (but how is that good?!)

 

Ben 10: Classics (Alien/Monster Transformations)

When the very first Ben 10 cartoon came out it was accompanied by a spin-off comic that ran in Cartoon Action Pack. Those comics were eventually collected in trade-paperback as the Ben 10 Classics series. In volume one, Ben Here Before, the artists render sequences of Ben's transformations into:

Grey Matter:

Four Arms:

Ripjaws:

and Upgrade:

Volume 02, It's Ben a Pleasure, has yet more alien transformations, this time into...

Cannonbolt:

Stinkfly:

Four Arms (plus a reversion):

Benwolf (reversion):

Grey Matter:

Wildvine:

Benwolf once more:

Heatblast:

Stinkfly again (with a reversion):

and Wildvine again (and a reversion):

Ben 10 Omniverse (Alien & Monster Transformations)

Thanks to Andréssaurio Rex for recommending these scenes. The first video is compiled from three episodes: "Max's Monster" (S04E04), "Weapon XI" Part 01 (S06E09) and "Weapon XI" Part 02 (S06E10) and show Grandpa Max's old friend Phil seeking help to tame the monster lurking within and transforming into it:

 

 

Also from the last episode mentioned above is a scene of Kevin 11 mutating into his most extreme form: 

 

If anyone knows of more transformation scenes from this series (the earlier Ben 10 shows have been pretty well covered), please let us know. 

Ben 10 [2026 comic] (Alien/Monster Transformations)

Ben 10 returned to comics this year in a reboot series. The first issue shows his very first transformation (into Four Arms), when he's attacked by a zombie bear:

Don't worry, he transforms into Heat Blast and burns the bear. In the next issue he shifts from Heat Blast to Stinkfly:

Issue 04 has another Four Arms shift:

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Inayah—Life After Gods (Monster Transformation)

Our thanks to Eran on Discord for alerting us to this cutscene:

 

Ultraforce, Regular Show, and Arkham City (Monster Transformations)

Thanks again to Andréssaurio Rex for finding these clips.

Several monster/muscle growth transformations are in episode five of the 1995 cartoon Ultraforce, involving a villain named "Sludge," whose "normal" appearance is that of a blue anthropoid. The first one, actually a reversion, starts at 6:52, to which this video is cued. Then there's a transformation at 7:07, another reversion at 10:04, and a last TF at 10:50.

If you're in the mood for more sludgy monsters, here's a slime-blob TF from episode eight of Regular Show: Lost Tapes:

And continuing with sludge monsters, here's a scene from the video game Batman: Arkham City, where the Joker reveals himself to be Clayface in disguise:

Transformation Round-Up (Monster, Imp, Vampire and Muscle Growth Transformations)

 Thanks to Andréssaurio Rex for locating the first four clips in this round-up.

A monstrous "rager" TF from the video game Gears of War: Judgment:

A chimpanzee turns into an alien-chimp in episode 17 of StuGo:

Some vampire facial transformations from the Swedish horror film Frostbite (2006). The first is cued to 27:37, the rest occur at 01:01:38 and at 01:17:09 and concludes after an interuption at 01:17:45. 

From Rahan episode one, a bear-to-imp/gnome transformation:

Some comedic muscle growth found by Kevrai, from the Atomic Betty spin-off webseries Crash-Test Noah, episode six: 

And for a comedic bonus, some absurd muscle growth from this Japanese commercial, also found by Kevrai:

Vox Machina (Muscle Growth and Monster Transfomation)

Thanks again to Andréssaurio Rex for these recommendations.

Some muscle growth from season four, episode one:

 

And in this clip (from season four, episode four) a monster increases in size and grows wings:

The Guyver: Out of Control (Demon/Monster Transformations)

Thanks again to Andréssaurio Rex for recommending this anime feature from 1986. Two transformations occur at 6:32 and 6:58, and this video is cued to the first. There's also a third TF at 22:31. 

Tales of the Teenage Mutant Ninja Turtles (Blob/Monster Transformation)

Thanks to Andréssaurio Rex for recommending these scenes from episode 12 of the second season. They show the villain Roderick Underwood turning into "Muckman." The clip has been assembled from several discontinous scenes, so apologies if it's a bit choppy:

 

John Carpenter's Toxic Commando (Monster Transformation)

Here's the animated trailer for John Carpenter's Toxic Commando, "an upcoming ‘80s-inspired action-horror FPS game." Thanks again to Andréssaurio Rex!

Robotomy (Monster Transformation)

A robot somehow turns into a monster in the ninth episode of this cartoon. Thanks again to Andréssaurio Rex for the recommendation.

"Monkey Wrench" & "Primal" (Muscle Growth)

 From episode 4 of the webseries: After Beebs refuses Campion Ajax's offer and shrugs him off, the latter grows with wrath:

And continuing with the monstrous-muscle-growth theme, here's a scene of a male dinosaur hulking up, from Primal (season 3, ep. 10). Thanks to Mr. Rex for the recommendation.

"Biker Mice From Mars" & "Acme Arsenal" (Muscle Growth and Monster Transformations)

Andréssaurio Rex suggested featuring the muscle growth scenes from this '90s cartoon. Luckily for lazy people like myself, The Male Muscle Growth Archives has already assembled a compilation of them! Go directly to the video's description for the episode titles. 

Mr. Rex also recommended this short cutscene from the video game Looney Tunes: Acme Arsenal, which also features muscle growth and monsterism, so I've included it as a bonus:

Blood+ and Blood-C (Monster Transformations)

Our thanks to Andréssaurio Rex for these links. The first scene is from episode 49 of Blood+ (if the cue doesn't work, go to 6:36): 

The second is from episode 12 of its follow-up, Blood-C: