Axolotl Story Further Findings

I found out that the Axolotl story portrays an interesting timeline-based story after reading it again. This means that as time goes on,  the narrator slowly transforms into an axolotl as the tone turns darker. I've learned that the transformation is a slow process because the narrator becomes more crazy. The story starts out with a normal setting, and an average human visiting the aquarium. However, this human becomes more addicted to the image of the Axolotl until he becomes one. Even the guard that found him to be normal starts to see him as someone insane after he claims that Axolotl is slowly devouring him. The words that the narrator uses began to become "darker" words such as "abyss" and "slaves." However, at the beginning of the story, the narrator uses words like "smiled" and the phrase "spring morning" which represent a form of a lighter tone.