- Complete Monster: Toyman is a criminal with an unhealthy obsession with children who views the entire world as his plaything. Taking advantage of Superman's death, Toyman uses a giant robot spider to rob banks, then uses the robot to take a school bus full of children hostage, threatening to drop the bus off a building if the cops don't let him keep the money. Lois Lane manages to save most of the kids, but a robot toy on the bus prevents her and one of the children from leaving. Seeing that most of the children he kidnapped have escaped, Toyman attacks Lois and the child. Toyman's robot throws the bus off the building with Lois and the child on board before being captured. Toyman quickly escapes from the police and attacks a day care center, where he kills a four-year-old.
- Harsher in Hindsight: Lex Luthor had invented a cure for muscular distrophy, but withholds it until he can modify it to be more profitable. In Justice League: Gods and Monsters, Lex appears to be in bad need of that medicine himself.
- Ho Yay: Lex Luthor's obsession raised quite a few eyebrows. His interactions with clone Superman in the red sun room don't help matters. It's one thing to use a red sun room and Kryptonite-knuckled gauntlets to beat up a Superman clone while shirtless, even if it concludes with straddling the supine Superman clone to taunt "who's your daddy", it's another to grab him and wail, "Why did you leave me? WHY?!"
- Memetic Mutation: "And you are on MY NAUGHTY LIST!"
- Nightmare Fuel:
- Toyman killed a child. This is horrifying enough on its own, but it also becomes the catalyst for clone Superman's Start of Darkness, as he decides to make an example of Toyman and stays in that mindset for the rest of the film.
- Clone Superman walking into a random barber shop and performing brain surgery on himself.
- When Clone Superman rescues the cat, you're not sure if he's gonna return the cat to the old lady or kill it in front of her.
- Squick: Suspicious of Luthor, Clone Superman casually walks into a beauty parlor and sits at one mirror in what at first is a really bizarre scene. He then uses his x-ray vision to spot the kryptonite encased in lead that Luthor planted in his brain. He then surgically removes it with his heat vision and a pair of scissors. We don't see any of this, but it's no wonder one of the workers fainted.
- They Wasted a Perfectly Good Character: Despite being the titular character, Doomsday is killed off halfway through the film with no hint of him coming back.
- They Wasted a Perfectly Good Plot:
- The film could have had a more compelling climax if Doomsday came back to life, forcing Superman and his clone to team up and defeat him in a more permanent fashion.
- With the Superman clone gradually turning bad, he could have eventually transformed into Bizarro.
YMMV / Superman: Doomsday