BROTHER ISAAC

Real Name: Unrevealed; first name might be Isaac

Identity/Class: Alternate reality (Earth-39943) human mutate

Occupation: Cult leader

Group Membership: Church of Abaddon

Affiliations: None

Enemies: Champion (Dan Taylor), Demon (Keith Greyson), Cheryl Greyson, Chris, Mike, Stan

Known Relatives: None

Aliases: None

Base of Operations: New Orleans

First Appearance: Demon's Tails#1 (January 1993)

Powers/Abilities: As a human Brother Isaac was a charismatic man able to sway dozens of people into joining his cult; he was also very muscular, suggesting above average though not superhuman strength.

   In his transformed state he had superhuman strength and durability, claws, fangs, an elongated tongue and a long tail. He also grew rapidly until he was around 40' tall.

 

Height: (human) 6' (by estimation); (transformed, at largest) 40' (by estimation)
Weight: (human) 220 lbs. (by estimation); (transformed, at largest) 24 tons (by estimation - see comments)
Eyes: Green
Hair: Black

 

History:
(Demon's Tails#1 (fb) - BTS) - Brother Isaac was the leader of the Church of Abaddon, a demon-worshiping cult based in New Orleans. Publicly registered as a church, they secretly committed ritualistic murders in the belief it honored their unholy master, but had recently suffered interference from Demon, a mutated man whose hirsute, three-tailed form bore an uncanny coincidental resemblance to the church's statue of Abaddon.

(Demon's Tails#1) - Isaac met with some of his cult's senior members to discuss progress, informing them that the cult's following had increased greatly in numbers of late. One of the cultists demanded to know what they were going to do about the "freak" (Demon), but Isaac told him not to get too riled up, stating that if he gave them any trouble he would send the masses after him by denouncing him as a false prophet. At that moment the meeting was interrupted by the arrival of some robed cultists, newly returned after being sent out to procure victims. They joyously informed Isaac they had seen Abaddon himself (still just Demon), who had instructed them to quit murdering people. Enraged, Isaac denounced them as blasphemers, and ordered the cultists he was with to get the robed ones out of his sight and kill them. As they were dragged off protesting that they were telling the truth, the other senior members insisted they should start taking Demon more seriously, suggesting that perhaps he was a sign from their lord, and whether freak, false prophet or demon, he might be able to provide them with answers. Agreeing, Isaac ordered Demon be brought to him. 

(Demon's Tails#2 (fb) - BTS) - The unfortunate cultists who had listened to Demon were crucified, their bodies left on public display. Seeing a TV news report about this, Demon decided he had to confront the cult more directly. Isaac meanwhile sent out some of his cultists in their robes, fully expecting Demon to eventually find one of these lures, and armed them with high-frequency whistles, suspecting that this might incapacitate the animalistic Demon. Isaac's suppositions proved correct, and soon some of the cultists returned with an unconscious Demon.

(Demon's Tails#2) - Dismissing everyone but his inner circle, Isaac examined his unconscious prize. As he observed, one of the inner circle, an older balding man, drew some of Demon's blood with a syringe and then injected it into two caged animals, a rabbit and a dog. While the cultists waited to see the results, Isaac ordered them to place Demon in a jail cell. With their captive out the way, Isaac and his lieutenants watched as the two test animals started to foam at the mouth and display extremely aggressive behavior. Isaac was impressed at what he considered the power on display, but then the cages began to jump as the beasts started to grow. Suddenly the rabbit and then the dog both ripped apart their cages, crashed around the room deliberately smashing objects, before the hound crashed clean through an exterior wall, with the rabbit swiftly following through the resultant hole. While the others were shocked, Isaac was elated, declaring the power displayed a gift from Abaddon. The balding cultist concurred, and suggested that Isaac could have the power himself if he injected himself with Demon's blood. Isaac readily agreed, declaring they would immediately get some more blood from their captive, but when they went to his cell they found he had woken despite being heavily sedated, and had escaped by ripping out the bars from his cell's windows. Angrily Isaac ordered his cultists to find Demon and get more of his blood.

 

(Demon's Tails#2 - BTS) - Out of sight of Isaac and the cultists the two animals collapsed, writhed in agony, and then literally dissolved.

   Elsewhere, having staked out Demon's home, Isaac's cultists witnessed a woman visit the house. They abducted her intending to deliver her to Isaac for sacrifice, unaware she was Demon's sister, Cheryl. 

(Demon's Tails#3) - The cultists presented Cheryl to Isaac, who declared her ideal for their purposes.

(Demon's Tails#3 - BTS) - Out in the city Demon confronted some of the cultists some of Isaac's cultists intending to get answers out of them, but was confronted by a costumed crimefighter, the Champion, who believed Demon was attacking an innocent man. Both of them were then rendered unconscious by the cultists using the sonic whistles, and taken back the Church of Abaddon.

 

(Demon's Tails#3) - Isaac prepared for the ceremony, donning his ceremonial robes and, despite the concerns raised by one of his lieutenants, injecting some of Demon's blood directly into himself. Then he ordered his minions to prepare their female victim. Once she was laid out on the sacrificial altar in the next room and tied down, Isaac entered to greet his supplicant cultists, announcing to those gathered that there would be a sacrifice and drinking of blood. Walking over to Demon, who had been hung upside down on an inverted cross, Isaac cut the prisoner's arm gathered some of the blood that flowed into a bowl, and drank it. Moments later, as Demon was desperately trying to appeal to the cultists' reason, Isaac suddenly turned to face them, revealing he was transforming, his ears growing pointed, fangs sprouting in his mouth and fingernails rapidly changing into elongated claws. Holding aloft the same blade he had cut Demon with, he declared it time for the sacrifice, and despite having to pause to handle spasms of intense pain, he loomed over the prostrate Cheryl and prepared to gut her.

 

(Demon's Tails#4) - Three of Demon's friends, Chris, Mike and Stan, had infiltrated the ceremony disguised as cultists, and freed Champion. Before Isaac could stab Cheryl the crimefighter barreled into him, then rapidly untied Cheryl while Isaac was getting back up. Affronted at someone interfering with his "sacred" ceremony and with the transformation making him increasingly and irrationally aggressive, when Demon taunted Isaac backhanded the captive, breaking the cross and sending Demon flying across the room, unintentionally freeing him too. Meanwhile Isaac's transformation continued, increasing in size and growing a tail. Now towering over everyone, Isaac declared that the ceremony had to be completed and the girl be slain with the sacrificial blade. As Chris, Mike, Stan, Cheryl and most of the cultists fled, Champion and Demon attacked Isaac, who had in only a few seconds had now grown so large he was barely able to fit in the room. Despite this they dodged his blows and managed to get a few strikes in against vulnerable spots, managing to hurt him a little, prompting a backhanded swipe from Isaac that sent both men flying backwards out the window. Rising to his full height, Isaac broke through the ceiling of the building. Now close to thirty foot tall, he grabbed Demon and tried to throw him, but Demon hung on to Isaac's fingers, so Isaac prepared to smash him with the other hand.

   Demon leapt from the open palm just before Isaac's other hand struck it, and punched Isaac in the face. Demon dropped back to the ground next to Champion, and they noted that Isaac, now doubled over in pain not from the blow but his continued transformation, was still growing. While his head was close enough to reach the pair struck him in the face simultaneously, but though he reeled backwards, it looked as though even this wouldn't be enough to end the fight. Then Isaac, his nose bleeding, appealed to Abaddon offering his service, and collapsed face first. Demon's friends, including Cheryl, risked coming over to Demon and Champion as they stood by the now prone but still enormous Isaac, and enjoyed a brief reunion, but then Champion drew their attention back to Isaac, pointing out that the cultist's massive form seemed to be melting. Seconds later they watched in horror as his body suddenly liquefied, turning into a gloopy slop. 

 

Comments: Created by Roland Mann, Paul Pelletier and Tom Romano.

   Annoyingly, the only cultist named is Brother Isaac, which makes discussing their individual actions and who does what fairly tricky. Would it have killed the creators to have them mention each others' names just once?

   ASSuming that Isaac's weight increased with his height then he would have weighed several tons by the end, BUT this isn't the Marvel universe, where extra mass is sourced interdimensionally by size changers. Isaac certainly didn't have time to consume anything to gain extra mass, so it's possible that his size increase was akin to a balloon expanding, taking up more space but effectively spreading his available mass thinner and thinner, which might account for why he suddenly dissolved - basically, the balloon (all his individual expanding cells) popped.

   This profile was completed on 09/12/2026, but its publication was delayed as it was intended for the Appendix 25th anniversary's celebratory event to represent Demon's Tails.

Profile by Loki.

CLARIFICATIONS:
Brother Isaac has no known connections to:

images: (without ads)
Demon's Tails?4 p2, pan1 (main image)
Demon's Tails#1, p15, pan5 (human headshot)
Demon's Tails#3, p18, pan1 (human body)
Demon's Tails#3, p22, pan6 (transforming)
Demon's Tails#4, p8, pan1 (with tail)
Demon's Tails#4, p17, pan1 (giant form)

Appearances:
Demon's Tails#1 (January 1993) - Roland Mann (writer), Paul Pelletier (pencils), Tom Romano (inks), Dan Danko (editor)
Demon's Tails#2-4 (February-April 1993) - Roland Mann (writer), Paul Pelletier (pencils), Thomas Florimonte (inks), Dan Danko (editor)

First Posted: 09/21/2026
 Last updated: 09/12/2026

Any Additions/Corrections? please let me know.

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