- Moderate
- Season 4 deals extensively with the trauma of a main character, who is strongly hinted to have PTSD. The flashbacks this character has include getting attacked by a ghost-like figure and drowning; these flashbacks can be disturbing and frightening to viewers.
- There are multiple scenes throughout the show that can be considered very intense and frightening in nature.
- The series includes themes such as social unrest, civil war, terrorism, anarchism, murder, and suicide.
- This show deals with very serious themes and occasionally depicts somewhat intense acts of violence.
- Some characters hold the ability to 'blood bend' characters. When a character is being blood bended, they're movements are unnatural and can be disturbing.
- The main villain of Season 1 can be frightening to younger children under 5. He wears a mask, and is very mysterious. The main character has several nightmares involving him.
- A lengthy flashback reveals a dark and somewhat disturbing past for one of the main characters. The entire flashback can be intense.
- An important character commits a murder-suicide in Season 1 by purposefully blowing up the boat that he and his brother are riding (just shows explosion from afar).
- The spirits depicted in Season 2 vary wildly in character design. While some spirits are harmless and cute, others are grotesque, some can be frightening and very intimidating in nature.
- The main villain of Season 3 kills an important character by suffocating said character with air bending
- The main character of the show is poisoned,when poison is forcefully introduced in her body. It depicts in detail not just the forceful poisoning, but also the main character's subsequent suffering as a result of the poison.
- The main character ends up confined to a wheelchair (though not permanently) by the end of Season 3 as a result of the poisoning and fight that took place during the finale.