Diablo's death in Suicide Squad comics was a result of a powerful confrontation with a major villain. His powers were overwhelmed, leading to his demise.
The length of the Suicide Squad story really depends. If you're talking about the comics, it's been told in multiple arcs and issues over the years. But for the main movie, it's about two hours of screen time.
Yes. But the availability of new Suicide Squad comics can vary. It could be part of a new series, a continuation of an existing one, or a special one-shot. You might need to keep an eye on comic book stores or online platforms for the latest releases.