Despite the series began with a softer and lighter tone, the show got considerably darker as the story developed, mainly on the ongoing films.
Season 1
- When Max first develops his powers in the first episode, his uncle puts him into the "Turbo Chamber", claiming to be "for his own safety". He proceeds to nearly blow up before Steel comes. This sequence involves glowing chainlike objects surrounding and attaching to him, which he proceeds to blow up. (more horrifying in hindsight, when comparing it to the end of season 2.) Not mentioning that if Max is away from Steel for eight hours, Steel runs out of battery and Max blows up due to energy overload.
Season 2
- Makino's armada of evil Ultralinks are an example of this. The Ultralinks are a race of parasitic entities that are constantly searching for potential hosts to bond with, ranging from inanimate objects to living beings. In the second season, few human characters are bonded with Ultralinks and the linking scenes are rather unsettling, as the characters are shown screaming in agony while being weaponized. If the bond is not broken in time, the Ultralink will permanently take over its host and they will force them to fight for Makino's glory.
- Toxxon’s genocidal plans. He dupes an ultralink into becoming Avatack whom he uses to take control of everyone in Copper Canyon playing the Max Steel videogame. This becomes a bleak hostage situation when he reveals that in fifteen minutes, if none of the players destroy Max then Avatack unleashes a pulse that, through the special controllers, would kill everyone playing.
Animated Films
- Morphos, the main antagonist of Dawn of Morphos and Maximum Morphos. Out of Max's enemies, he is probably the strongest (likely stronger than Makino, as N-Tek predicted that he could become an even bigger threat than Makino himself) due to his "Reactive Adaptation", which allows him to copy any ability or power of his foe. While he is initially created with the intent of destroying Max and N-Tek, Morphos slowly develops his own conscience and agenda, to the point where he gets aware of how powerful he is and nearly kills Dread in a rather sadistic fashion after copying his abilities and trying to end his life with his own powers. He is also shown to be just as intelligent and treacherous as Miles, and to make matters worse, he is indestructible and immortal. The series website also once stated that he would be the future rule of the world. Basically, Miles Dread doomed everyone on the Max Steel universe by creating Morphos.
- Morphos' clones in "Maximum Morphos" also have a pretty scary and unsettling design, which closely resembles the Regenerators from the Resident Evil franchise.
- Mortum. After his mutation, he goes from a genius scientist from a insane robot zombie with a hunger for brains. All of his forms are based on creepy animals, such as scorpions, bats, centipedes and spiders. Besides, Mortum is immortal and cannot be destroyed thanks to his Connect-Tek armor, which allows him to regenerate himself into endless combinations.
- At the end of the Team Turbo film, when the Connect-Tek is overloading on Mortum, his bones are partially shown while he screams in pain and agony. Mortum's mutant form also features this. For instance, he wasn't only killed by the Connect-Tek, but the device itself gets fused to his skull. He also seems to be more focused on his goal and doesn't shows any compassion or empathy towards anyone, to the point of almost converting his own nephew (apparently being his favorite prior to his insanity state and mutation) into a mindless zombie.
- Turbo-Warriors has a brief moment when Terrorax decides to show to Max how a world dominated by Nexus would be. In this vision, the world fell in anarchy and chaos, Max's friends were killed by Nexus soldiers and Maxwell, the main protagonist of the show, is rulling the humanity alongside with Terrorax and lord Nexus while many Nexus agents are gloryfing them. It's not simply scary, but heart-breaking, as you never expect the heroes to lose the battle against villains, no matter what happens.
- The aforementioned Terrorax also has macabre designs used for the toy line. His main form is a cross between a clown, a gargoyle and a demon, besides, he also has a permanent slasher smile revealing his mouth of spiky teeth. His mini Dark Dragon form used by the end of Turbo-Warriors also has a disfigured human skull for its face.
- Snare, the "lethal assassin robot". As he stated on Turbo-Charged, he has killed many persons over the years and nobody ever managed to escape from his hands. He has access to many dangerous weapons that he uses to torture and kill people. Worst part is that he wasn't dealing with any superhuman individuals, meaning that he was killing innocent and defenseless people who had the bad luck of crossing paths with him.
- Team Terror as a whole counts as this, as they are confirmed to be assassins and who knows what they were doing before they joined the Nexus.
