Strange Alien Lifeforms
The Strange Alien Lifeforms unit is led by Captain Gedorian, mostly consisting of alien lifeforms and animals.
Toad-like parasites that thrive in warm areas, able to spew foam from their mouths that induce a high fever in their human victims before laying their eggs in them so they can serve as both incubators and their offsprings' first meal. Three Culculten hatch, using the Sahara house as their base of operation and attempt to kill Kotaro until Shigeru uses ice cubs to drive them off. When encountered again, the Culculten manhandle Kotaro until he becomes RX to out wrestle them before using the Revolcane to kill them each, with the effects of their foam wore off.
Episodes 6 & 45
A cactus like alien sent by Gedorian without Jark's consent to turn the Sahara family in cacti-slaves that attack RX until he is forced to fall back when the effects wear off. But Maribaron offers her aid to Gedorian by tricking a girl named Chika into giving up her life to Atechpetchy so his power can be perfected. But RX ruins the scheme and use the Acrobatter to destroy Atchpetchy with his Revolcane.
Episode 9
A slithering blob-like monster with tentacles for arms, able to spray his slime on them with the slime morphing into a clone. Dogmalogma uses his power to create clones of Shigeru, his frieds, and Reiko as part of Maribaron's plan to use those Kotaro trusts against him. But once he becomes RX, his Kingstone causes the clones to dissolve before he battles Dogmalogma. When the monster attempts to engulf his hostages, RX stops and Dogmalogma kills him with the Revolcane.
Episode 10
A jellyfish-like alien parasite with teleportation abilities sent to obtain the G Crystal that was stolen by a rogue Crisisian scientist and his daughter Kirara, with RX driving him away as Kirara learns the G Crystal is found by Shigeru and Kengo. Flarmiglarmi later enters Kirara's body, getting the G Crystal from Shigeru as Kotaro arrives. In spite of warning Flarmiglarmi the danger the G Crystal poses for both worlds, RX is forced to fight him with the Arcobattler before killing him with the Revolcane to destroy the G Crystal and the machine it powered.
Episode 13
A flying squirrel/bat monster. It can breathe fire, use its fangs to inject a toxin, and shoot electrical beams from its eyes. It was used to turn Shigeru and other children into vampires. Kotaro ended up bitten by Shigeru and during a battle with Musalabisala, he was bitten again. Kotaro became Bio Rider to get the injected fluid out of him. Kotaro tricked Musalabisala into thinking that he fell under his control. The trick worked, allowing Kotaro to henshin into Kamen Rider Black RX and fight him. Musalabisala had RX in a pinch until Joe threw one of his sais at him. Kamen Rider Black RX used the RX Kick on Musalabisala before destroying him with the Revolcane. He returned in the Kamen Rider Black RX movie to assist Deathgaron, United Triplon, and Gynagiskhan in their attack on the Kamen Riders only to be destroyed by a team Rider Kick.
Episode 18
A blue monster who can shapeshift and transform into a shadow. He attacked Joe while he was with an old friend of his named Saila in an attempt to obtain her necklace and ended up injuring Joe in the process. Luckily, Kotaro transformed into Kamen Rider Black RX and battled Bang-Gong. Kamen Rider Black RX got them to safety in Ridron which also tackled Bang-Gong. Bang-Gong later kidnapped Saila. When Joe and Kotaro found her in an abandoned warehouse, they were ambushed by Bang-Gong and the Chaps. Kotaro transformed into Kamen Rider Black RX and fought him. As Bang-Gong swiped the necklace, Kamen Rider Black RX became Bio Rider and followed him outside. Bio Rider took back the necklace and then called forth his Bio Blade, which he used to cut off Bang-Gong's antennas and then kill him. He then got Joe and Salia out of the warehouse before the bomb planted by Gedorian blew it up.
Episode 21
A white-haired ant monster. He can create tornadoes and manipulate soil and use it to bury people. He attacked a playground and its surrounding areas until Kotaro and Joe arrived to stop him. Kotaro transformed into Kamen Rider Black RX to fight him (with Shadow Moon secretly observing the battle). When Ant Runt created a boulder, Kamen Rider Black RX became Robo Rider. However, Robo Rider proved useless against Ant Runt as the monster clogged all of Robo Rider's joints with dirt. After transforming into Bio Rider however, he easily maneuvered against Ant Runt causing the monster to retreat and saving everyone who had been buried. He and Gedorian later crashed the battle between Bio Rider and Shadow Moon. Ant Runt trapped Bio Rider and Shadow Moon in an anthill. Ridron freed them and Bio Rider turned into water to attack Ant Runt. He then reverted to Black RX and destroyed Ant Runt with the Revolcane. Antrunt was later revived by Maribaron as part of the Spirit World Kaijin Army.
Episodes 22 & 45
A monster resembling a lobster, with scythe-blades for hands and lobster legs between its upper back and shoulders. It assisted Gedorian in his plan to turn the people into vampires. When Kotaro stumbled upon one of the victims attacking people in the car, he saved them before Lickback attacked. Kotaro transformed into Kamen Rider Black RX to fight Lickback before the monster retreated. After an ambush by Chaps, Kotaro transformed into Kamen Rider Black RX and fought Lickback and the Chaps while Joe tried to free Lickback's hostages and fight off the victims at the same time. A kick at Lickback revealed a glowing part on its body. Kamen Rider Black RX used his Revolcane on that part destroying Lickback, thus freeing his vampire victims.
Episode 24
A white-haired anteater monster with crab claws for hands. The Crisis Empire used it to dig into a mountain to cause a volcanic eruption until Shadow Moon took control of it. When Kamen Rider Black RX encountered Matbot, it attacked the other Crisis Empire officers who fought back. Kamen Rider Black RX escaped the cave-in and ended up engaging Shadow Moon in battle. Gedorian disciplined Matbot at their base and General Jark told Gedorian to use Matbot to capture two children for revenge on Shadow Moon. After defeating Shadow Moon, Kamen Rider Black RX became Robo Rider and fought Matbot underground, who then went above ground while Robo Rider disarmed some bombs. Acrobattler tackled Matbot and Robo Rider used his Vortech Shooter to blast off his right arm. Robo Rider then reverted to Kamen Rider Black RX and destroyed Matbot with the Revolcane.
Episode 27
A scaley ostrich/dragon-like creature that had small dragon-like heads for hands and an extra mouth on its belly. He can breathe fire from his main head, shoot electricity from the dragon-like heads, breathe steam from the extra mouth, and attack with his tail. Crisis Empire used Gimelagomela to turn people into butterflies and infect them so they could control them. When it attacked a small boy, Kamen Rider Black RX came to save him and battled Gimelagomela, but the victims arrived to help him. Kamen Rider Black RX called for Acrobatter to tackle Gimelagomela but he used his steam attack on him. General Dasmander appeared to have his fight with Kamen Rider Black RX and told Gimelagomela to stay out of it. During the battle, Gimelagomela and his victims interfered and attacked Kamen Rider Black RX. When Kotaro followed the butterflies to their source, Gimelagomela attacked again. Kotaro transformed into Kamen Rider Black RX and fought Gimelagomela. Kamen Rider Black RX used his RX Kick on Gimelagomela, then destroyed him with his Revolcane.
Episode 28
A flea-like monster. He can launch a stinger from his mouth and shoot lasers from its eyes. Mundayganday was the one responsible for killing Kyoko Matoba's parents. He, Gedorian, and the Chaps were attacking a reservoir in an attempt to stop the flow of water into the city because Maribaron was delivering water to people. When Kotaro, Reiko, and Kyoko arrived at the reservoir and were attacked by Mundayganday Kotaro transformed into Kamen Rider Black RX and fought him until Gedorian and the Chaps trapped him a slime-like substance shot from their guns. Kamen Rider Black RX became Bio Rider and destroyed Mundayganday's exo-skeleton with his Bio Blade. He then reverted to Kamen Rider Black RX and destroyed Mundayganday with his Revolcane.
Episode 29
A brown lobster-like monster with octopus tentacles on his hips and smaller ones for hair. He can shoot lasers from his claws. He assisted Crisis Empire when they tried to blow up Setoo Bridge. When Kotaro confronted Gazolagezola on a boat, he transformed into Kamen Rider Black RX and discovered Crisis Empire's plans during the course of the battle. As Bio Rider, he used his Bio Blade on Gazolagezola's stomach, removed the time bomb inside him, and threw it into the water. Gazolagezola went underwater and Bio Rider turned into water to follow him to shore. After getting out of Gazolagezola's trap, Bio Rider followed it and reverted to Kamen Rider Black RX. He used his RX Kick on Gazolagezola before destroying him with the Revolcane.
Episode 33
A one-eyed alien monster with an elephant-like trunk for a mouth. It can shoot a beam from its eye, and spew steam from its trunk. It disguised itself as a masked wrestler and brainwashed kids into rooting for him, including Shigeru and his friends. When fighting in a re-match against his latest opponent, it turned out that Bio Rider had merged with Balunbolun's opponent and so he shed his disguise. As the boxer got everyone out of the building, Bio Rider fought Balunbolun who made off with a small boy. After turning into water and catching up to Balunbolun, Bio Rider reverted to Kamen Rider Black RX and fought him. Acrobatter tackled Balunbolun freeing the boy. Kamen Rider Black RX then used his RX Kick on Balunbolun before destroying him with his Revolcane.
Episode 36