Killzone is a fan-made 40k supplement, currently on its third iteration.
There are two (or more) documents that define how lists are built and how the game is played.
There are a TON of composition rules in Killzone (presumably for balance), but they seem counter-intuitive and sometimes raise more questions than they answer.
An example: An Imperial Guard Kill Team can have a maximum of 2 Heavy Weapons Teams. Ok, no problem. BUT, where do I pull them from? My choices.
-2 Infantry guardsmen (from an Infantry squad) 10 points+weapon.
-2 Veteran guardsmen (from a Veteran squad) 14 points+weapon.
-Heavy Weapons Team (from a Heavy Weapons squad) 20+weapon.
*Admittedly, the costs for teams are different, but if I can get a BS 4 autocannon for 24 points and a BS3 autocannon for 25 points, something is wrong.
Also, the "Theme lists" are not viable. There exists a theme called "brutes" or something that lets you take all of your choices as 3 wound models. (The example they give is a kill team of all Ogryns) BUT, you still must abide by other rules. Each Ogryn has a Ripper Gun, an Assault 3 weapon. So, taking more than 3 Assault 3 weapons is a violation, immediately invalidating an all-ogryn army, which is what they used as an example! Ye gods.
I played two games with a friend. In each game, neither the Primary, Secondary, or Tertiary objectives mattered, one of us had been tabled by the time turn 4 came around.
My review. Not balanced. Not incredibly fun.
While I am not a big fan 0f home-brew rules, it is apparent that a lot of work went into this, but it still falls short in many ways.
If anyone has had a different experience, I would love to hear about it.