- With his white Japanese Navy uniform, katana, black hair and stoic, non-nonsense personality, Kakugo resembles a bespectacled version of Shutaro Mendou of Urusei Yatsura.
- A lone, ripped fighter with short dark hair, whose name starts by K and who uses a supernatural martial art, travels through a post-apocalyptic world after a nuclear war while fighting nasty brutes. He pursues a former acquitance and user of his same martial art who betrayed him, left him with scars and took a loved one away from him. It's also discovered that said baddie's mind was corrupted by another baddie. Kakugo in Apocalypse Zero or Kenshiro in Fist of the North Star? Even Kakugo's seven Steel Balls are placed in direct reference to Kenshiro's seven scars.
- Kakugo's Tactical Evil form is a reference to Devilman's title character, not only visually, but also because, like him, Kakugo manages to take over his demon body and use it to strengthen himself.
- The luminous tentacles, the bugs healing Kakugo and the bugs that absorb radiactivity at the end of the series all evoke Nausicaä of the Valley of the Wind.
- The Fortified Armor Shells are basically human-made, steel-coated Guyver armors. The lead also uses his own to fight mutated humans turned into monsters (Tactical Evils in Zero, Zoanoids in Guyver).
- A lone, ripped fighter with short dark hair and who carries a sword travels a dark world while fighting nightmarish monsters who used to be humans, and the very first monster he faces onscreen is a horrid, sexually deviant female, which he kills by piercing through her mouth. Kakugo in Apocalypse Zero or Guts in Berserk?
- The Shout-Out also works in reverse. Chidokuro's helmet may resemble Femto's, adding to his grafted female breasts feeling like a jab to Griffith's androgyny, and his sexual abuse of Tsumiko also feels like a parody of Femto's most infamous deed towards Casca. Eikichi is also similar to Wyald, an old man turned into a lecherous, abrasive monster with a weaponized penis. However, in a subversion, the Berserk chapters featuring Wyald and the Eclipse came out one year after Apocalypse Zero had concluded. Those developments only made Guts resemble Kakugo even more, as he now pursues a former acquitance of him who was a bishonen genius and his superior in fighting, who later betrayed him after being corrupted by a dark entity and becoming a human demon, and who also took a loved one away from him.
- One of the manga Tactical Evils is a monstrous parody of Sazae-san, sporting the name of Sazae and featuring several heads based on the family's members.
- Chidokuro's appearance is also near-identical to the titular character of Phantom of the Paradise, which matches him being confronted in an amusement park.
- The main antagonist is an AMAB character who changes gender to get more powerful and, breaking some of the worst stereotypes of the era, is easily one of the biggest stand outs of the series; a nigh-invincible Visionary Villain whose gender change is never ridiculed or vilified, and who honestly appreciates their minions (to the point that their lover is a male underling)— in fact, their defeat is only possible after they dedicate too much love to somebody else... This definition could either belong to Harara Hagakure, or Dongfang Bubai from the Swordsman seriesnote .
- Frank Herbert's Dune, another work with ecologist themes set in a faraway future, lends a ton of visible inspirations.
- The armors' life support system is very similar to how stillsuits are described. Being living bio-suits composed by multiple entities, they also resemble Leto II's trout suit in Children of Dune.
- Many of Oboro's philosophical lectures sound straight out of Dune, but the quote about how "people who only want to live on are not more than animals" is a direct reference to the Bene Gesserit creed. The armors' collective conscience of dead people evokes the Other Memory, the explanations about Zero martial art sound a lot like Prana Bindu, and Harara's kiss is described in similar terms to imprinting or neuro-seduction.
- The horribly obese, perverted Hamuko also reminds of Baron Harkonnen in both things.
- As in Children of Dune, the manga stars two siblings of different sex, among which the female is possessed and becomes evil by action of a similarly evil ancestor.
- Shiro Hagakure, while clearly referencing by name the infamous Japanese scientist Shiro Ishii, is clearly inspired on Yasunori Kato from Teito Monogatari, another undead Japanese Imperial Army officer who tried to use his offspring to cause mayhem (and whose offspring eventually turned against him). He's even drawn with Kato's seiman pentagram-decorated white gloves.
- Similarly, just like Kato was possessed and powered by the grudge of the people killed by the Japanese Empire, Harara is possessed by the grudge of the victims of Shiro's experiments.
- Tsumiko is possessed and turned into a monster, just like Yukari Tatsumiya.
Other
- Classic tokusatsu elements, especially from the Kamen Rider franchise and the Ultra Series, are also thrown together.
- In reverse, Jin Saotome from Cyberbots (and, later, Capcom vs.) is an Expy of Kakugo. They even wear the same scarf.
