Acht

"Everyone, meet Dedf1sh. Previously a promising, up and coming DJ, her pursuit of breakbeat perfection eventually led her to a subterranean test facility, where she was "sanitized." Though little of her former self remains, she continues crafting DJ delicacies, and the halls of the test facility echo with her bumping tracks to this very day."

- Live from the Squid Research Lab

Dedf1sh is a musician in Splatoon 2 whose songs were released as part of the Octo Expansion. Once a normal Octoling, she entered the underground test facility and became sanitized, losing her free will.

Songs
Before the release of the Octo Expansion, a video entitled 'Catalog Mix' featuring short sections of some of the songs was made available. It includes several songs heard in the Octo Expansion and its missions. The only song that was named prior to Octotune's release was Splattack! (Octo).

Trivia

 * In her album art, Dedf1sh uses a series of turntables each with the number 8 on them and eight buttons, corresponding to an octopus' number of arms and the overall recurring number eight through the Octo Expansion.
 * The background of the album art features the Kamabo Corporation logo, also seen on places such as the CQ card and C.Q. Cumber's hat.
 * Dedf1sh's name may be a reference to the DJ and musician known as deadmau5.
 * Her name could also be a reference to the fact that Sanitized Octarians show no vital signs of life.
 * With the style of her tentacles, headphones, and colored fingertips, Dedf1sh bears a resemblance to Marina.
 * Oddly, her numbered catalog of songs appear to be missing select numbers: 3, 7, 10, 15, 17, and 18.
 * When adding the numbers from the title of each song and then dividing the total by the number of songs Dedf1sh has composed, the result is eight, the recurring theme of the Octo Expansion.


 * HaikaraWalker reveals that Dedf1sh's real name is "ミズタ アハト" (Mizuta Ahato); or Ahato Mizuta if written with the English name order, as surnames come first in Japanese.
 * A Q&A with the Squid Research Lab from the Nintendo Dream Magazine revealed that Dedf1sh wanted to become sanitized, so she could give up her doubts and conflicts about production and devote herself entirely to music.