Graffiti street art has always been a powerful medium for self-expression, and many artists have ventured into creating horror-inspired pieces to elicit a range of emotions from viewers. Horror in graffiti street art can be seen in various forms, including:

1. Dark Imagery: Artists may utilize dark, eerie, and sometimes grotesque imagery to evoke a sense of horror. This can include haunted houses, ghosts, zombies, or other supernatural beings.

2. Macabre themes: Themes related to death, decay, and the darker aspects of life are often explored in horror-based graffiti art. Skulls, skeletons, and other symbols of mortality can be prominently featured.

3. Surrealism: Surrealistic elements can heighten the sense of unease in horror-themed graffiti. The artist might create distorted, dreamlike, or nightmarish scenes to disorient and unsettle the viewer.

4. Pop culture references: Graffiti artists may incorporate well-known horror characters, such as Pennywise from "It" or Freddy Krueger from "A Nightmare on Elm Street," into their works. This creates a familiar yet unsettling atmosphere.

5. Psychological horror: Some artists may opt for a more subtle approach, using symbolic imagery or metaphorical representations to evoke a sense of dread or anxiety rather than outright terror.

6. Urban legends and folklore: Artists can tap into the rich history of urban legends and folklore to create chilling scenes that capture the imagination of passersby.

7. Social commentary: Horror-based graffiti can be a means of exploring and critiquing societal issues, such as violence, poverty, or political oppression. These pieces can serve as powerful statements that provoke thought and discussion.

Horror in graffiti street art allows artists to express their creativity while engaging with their audience on a visceral level. The combination of public space and unsettling imagery can make these works memorable and impactful, leaving a lasting impression on viewers.