Content & Trigger Warnings for Teenage Mutant Ninja Turtles (2012)

Splinter's tragic backstory involving the loss of his family is referenced

Splinter's past and his relationship with Shredder as former brothers is explored more deeply

Splinter faces mortal danger and the turtles confront the possibility of losing their father

Splinter's death is a major emotional event that deeply impacts the turtles

The turtles mourn and struggle to continue fighting after a devastating personal loss

The turtles still process previous losses while moving forward in their adventures

Shredder manipulates Karai by lying about her true parentage and allegiances

Villains continue to deceive and manipulate allies against the turtles

Kavaxas and other villains use deception and manipulation against the turtles

April O'Neil and other allies are captured by the Kraang and Shredder's forces

Characters are captured and held prisoner by the Kraang during the invasion arc

Multiple characters are captured during conflicts with the Kraang and Shredder

Characters are captured during various crossover and time-travel storylines

Characters are kidnapped regularly; April O'Neil is frequently captured by villains.

Large-scale battles against alien invasions become a major storyline.

Mutagen transformations turn humans and animals into mutant creatures, sometimes grotesquely

More disturbing mutations occur including the Kraang's biological experiments on humans

Karai's mutation into a snake creature is a disturbing and prominent storyline

Demonic transformations and mutant horrors become more visually intense

Various mutant creatures and transformations continue but with a lighter touch

Mutation storylines involve characters transforming into monstrous forms, particularly with mutagen exposure.

Characters are trapped in confined spaces during several episodes, particularly in the sewer setting.

Some episodes, particularly those with Kraang, feature sudden scary moments.

Karai is transformed into a serpentine mutant and snake imagery becomes central

Karai's snake mutation storyline continues in the background

Insectoid Kraang aliens and various mutant bug creatures appear regularly

Alien insectoid creatures continue to feature prominently in the Kraang storyline

Bug-like alien creatures continue to appear in various episodes

Animals are mutated against their will into hybrid creatures.

Animated martial arts combat with robots being sliced and smashed, no blood on human characters

Continued animated combat with increasingly dangerous foes and more intense fight choreography

Stakes are raised with more intense combat and the threat of planetary destruction

Darker tone with more brutal fights and a powerful demonic villain threatening reality itself

Lighter tone compared to season 4 with more comedic action and cartoon-style fighting

Characters use laser weapons and futuristic guns throughout the series.

Villains capture and torment characters in some episodes, though not graphic.