Trivia: John Ostrander, who created the Suicide Squad team in the comics, has a cameo as the doctor who implants the brain bomb into Michael Rooker Savant.
Trivia: Pom Klementieff, who plays Mantis in the Guardians of the Galaxy films, also directed by James Gunn, has a cameo here as one of the patrons inside the club on Corto Maltese.
Trivia: In the prison sequence, at one point a TV is visible in the background playing the famous and infamous cult-film "The Toxic Avenger." "The Toxic Avenger" was produced by the independent studio Troma Entertainment. Director James Gunn actually got his start working for Troma, writing the cult favorite "Tromeo and Juliet," and doing various other behind-the-scenes jobs on several other Troma productions. As a thank-you, Gunn often includes Troma easter-eggs in his films.
Trivia: King Shark was originally going to be a hammerhead, but director James Gunn found it challenging for a character with monocular vision to interact with other characters, so he went with the great white design instead.
Trivia: At one point, Amanda Waller says that she is supposed to play golf with Senator Cray. Cray is a notable character in the comics and after he dies, his son, The Atom, joins the Suicide Squad.
Trivia: A lot of people involved in James Gunn's "Guardian of the Galaxy Vol. 2" also appeared in, or worked on, Gunn's "The Suicide Squad." For example; Michael Rooker, Sylvester Stallone, Sean Gunn, Steve Agee, Stephen Blackehart, Pom Klementieff, and Terence Rosemore appeared in both films. And one of the rats that played Sebastian is named Crisp Ratt. Henry Braham and Fred Raskin did the cinematography and film editing for both films. Just to name a few.
Trivia: Warner Brothers offered James Gunn the opportunity to direct a sequel to Man of Steel, but he chose to do this film instead. Gunn would later go on to direct a new iteration of Superman with "Superman: Legacy."
Answer: It's a combination of various reasons. Will Smith wasn't available to reprise his Deadshot role, so there was a shift in the story. King Shark was intended to be in the first film, but the CGI was too extensive, so they went with Killer Croc. In this film, they took the opportunity to bring in King Shark as the "monster" character. But, this film isn't really a sequel or reboot. Basically, this is a new storyline with new characters, and many of the previous characters are just not in the film, with no exposition on what happened to them, and they may not even be part of this film's "universe." The fact that some of the actors play the same character in both films only serves to muddle the concept of this film not really being a part of the previous film's continuity.
Bishop73