Battlefront has posted the meat of the Dust Battlefield rules online, along with the special rules. You’ll also need the Tactics 2.0 rules to play, as Battlefield is essentially a “mod” (to use lingo from computer games) for Tactics to take it into open terrain. Additionally, you’ll need some Tactics cards, some of which can be found in each faction’s section on World of Dust.
Some might ask “Why buy the book if the rules are now online for free?”, but the advantage of the hardback book is that everything is in one place, as opposed to the somewhat haphazard release of the PDFs (which are only really meant to be previews anyway). Also, ink is expensive these days, so it’s probably cheaper to just buy the book when it goes on sale.
For anyone who might ask “UF? Posting Battlefield news?”, yes I’m willing to give Battlefield a shot. Although I haven’t played Battlefield yet, it does look like a different, lighter, game to Warfare that has its own niche. I’ve said before that Battlefield is not a replacement for Warfare; both games can co-exist as long as Battlefront supports them equally and players carry on playing them.