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* As a racecar driver, [[LawOfChromaticSuperiority Takeru or Red Mask]] was granted personal use of the [[CoolCar Spin Cruiser]] buggy, which was the only vehicle capable of foiling a monster's plan. After two episodes, he becomes proficient in the [[PowerOfTheGodHand God Hand]] maneuver. A little while later, he is not only Igam and Kiros's rival but also [[PlasmaCannon Jet Cannon's]] regular pilot.
* In episode 20, one of Emperor Zeba's most dependable henchmen--[[HypercompetentSidekick Earth Curiosities Beast Anagmas]]--steps in to deal with the Maskmen after [[GeneralFailure Baraba]] and [[TheStarscream Igam's]] countless failures. As the archivist and mystic of Underground Empire Tube, [[ManipulativeBastard Anagmas]] comes up with a [[EvilPlan successful plan]] to weaken Momoko, thus crippling Great Five and allowing Tube to seize the mecha.
** Anagmas is also able to approach and destroy the crystal ball that holds Zeba's secrets before the Maskmen and Ial discover it. He then stays behind to confront the Maskmen in order to buy Zeba some extra time to finish his grand scheme.
* Episodes 20-22 provide a back-to-back-to-back swathe of [[SugarWiki/MomentOfAwesome Awesome Moments]]. To wit:
** 20 features both Tube outgambitting the Maskmen to place Great Five under Tube control AND Momoko beating the piss out of a Doggler without transforming, even at the cost of fainting after the team use the Shot Bomber.
** 21 reveals the Galaxy Robo, a second mecha designed by a contemporary of Commander Sugata that failed to win the honor of primary combat mecha. It then went on a rampage and hid in the mountains, with Red Mask tracking it down and using it to drive back the Dogglers despite the rampaging AI.
** 22 sees the team finally figure out why the AI rampaged AND CLAIMED GALAXY ROBO VIA MEDITATING WITH IT BEHIND A MOUNTAIN. Afterwards, they finally reclaim Great Five from Tube.
* The Maskmen rescuing the stolen and "brainwashed" Great Five by commandeering the "rogue" mech Galaxy Robo. By the end of it, they've somehow gained two HumongousMecha instead of just one, making them an even more formidable force to reckon with against the Underground Empire Tube.
* In episode 27, it's the arrival of Thief Knight Kiros as the KnightOfCerebus of the season for the Maskmen.
** He made a real splash when first confronting the Maskmen by using his FinishingMove, the Crescent Screw and the power of the latest Doggler Beast to destroy the [[PlasmaCannon Shot Bomber]], which forced the team to find a suitable upgrade.
** He brings in a certain flair to his villainy with his [[VariableLengthChain chain weapon]], his [[SissyVillain flamboyant attire]], and his own hidden agenda to [[DragonsPreferPrincesses claim Princess Iyal as his own]], which is reminiscent of Prince Sincline's obsession with Princess Fala in ''Anime/GoLion''.
** He'd pass on such traits to characters like him in future series installments like Chevalier in ''Series/ChikyuuSentaiFiveman'' and Emperor Tranza in ''Series/ChoujinSentaiJetman''.
* The Maskmen managing to defeat a MonsterOfTheWeek without the use of the Shot Bomber, but at the cost of Commander Sugata's [[CastFromHitPoints lifeforce]]. To be fair, the Shot Bomber was destroyed in the same episode by Kiros.
* In episode 30, the special appearance of Earth Imperial Commander Baraba's mother, Laraba (played by Creator/MachikoSoga, who'd later play Bandora of ''Series/KyoryuSentaiZyuranger'' fame) to get the [[UnholyHolySword Imperial Underground Sword]] from Devil Doggler is as awesome as it is [[EvilMatriarch heartbreaking]].
** By the end of the episode, she showed her [[BrokenBase true colors]] as a woman who was more obsessed with her [[SocialClimber family’s standing]] as [[ProudWarriorRaceGuy proud warriors]] than that of [[WellDoneSonGuy Baraba’s well-being]]. However, her death in the hands of Devil Doggler [[HeroicResolve actually]] [[VillainousValour spurred]] her [[EvenBadMenLoveTheirMamas "weakling son"]] to defeat the monster and retrieve the sword.
* In episode 38, Igam tried to pull a ''Film/BackToTheFuture1'' or ''Film/TheTerminator'' style TemporalParadox by traveling back in time and attempting to kill Takeru when he was a child. She fails and HilarityEnsues with Takeru's child self ending up meeting the Maskmen, but you can't fault her for lack of creativity or tenacity.
* Let's talk about the [[MagnificentBastard villainous shenanigans]] of [[TheUsurper Earth Emperor Zeba]], the despotic ruler of Tube. He usurped the Igam Family and turned Underground Empire Tube from a pacifist kingdom into a militaristic dictatorship intent on annexing the surface world.
** Zeba, who was secretly Lethal Doggler's child, [[SelfMadeOrphan cannibalized his own parent]] as soon as he was born in order to [[CannibalismSuperpower inherit its abilities]]. Once in power, [[BadBoss the disguised Zeba]] used the [[ServantRace human population]] of the subterranean empire as slaves and regularly [[ElectricTorture hurled lightning]] to punish his own henchmen for their shortcomings.
** In the last episode, Emperor Zeba offers his [[MoralEventHorizon remaining subjects as sacrifices]] to bring the Underground Castle to the surface. From there, he can [[DepopulationBomb detonate the castle]] and unleash the evil particles within, [[HostileTerraforming transforming Earth]] into a [[AfterTheEnd desolate and hostile place]] that can only inhabited [[DancinInTheRuins by himself]].
** Although his death was [[AntiClimaxBoss anticlimactic]], Zeba did end up [[KarmicDeath reaping what]] [[SelfDisposingVillain he had sown]] by being such an [[CompleteMonster irredeemable villain]] who'd use his own henchmen as shields to [[DirtyCoward save himself]].
* In the GrandFinale, Iyal and Igam finally finally decide to [[BarrierMaiden join forces]] and use the [[MagicalAccessory Igam Family pendant]] to amplify the [[OverclockingAttack massive aura burst]] of the Maskmen, [[PowerNullifier destroying the evil particles]] and finally completely changing Zeba back into Lethal Doggler II in order to be destroyed by the Maskmen.
** Before the battle with the Galaxy Robo, most of the Maskmen's standard attacks weren't working against Lethal Doggler II until they started using special moves that purely use [[KiManipulation Aura Power]], like their [[ChargedAttack Meditation abilities]] and using the [[CombinedEnergyAttack Jet Cannon at FULL POWER]]. However, the cunning Zeba merely [[EnergyAbsorption absorbed the energy]] to grow in size without the help of Okelampa. The Galaxy Robo then makes [[AntiClimaxBoss short work of him]] afterwards.
** Even though TheUsurper Emperor Zeba is defeated and Takeru and Iyal end up together at last, their reunion is fleeting. She must [[BittersweetEnding end her relationship with him]] because she has taken over as Tube's new ruler. Igam herself decided to go on an [[TakingTheVeil endless pilgrimage as a priestess]] to atone for her sins.
** On the bright side, Takeru still has his friends waiting for him, and now that [[RightfulKingReturns Iyal is Queen]], Tube is no longer a threat, is likely to revert to its [[FisherKing previous peaceful state]], and may even be accessible to Earthling visitors. In other words, Takeru and his friends are free to visit Iyal whenever they please.