The Horus Heresy, 30k, will be a seperate game box game much like Space Hulk and Execution Force. It's also coming very soon.
A very a solid source here on this site, has chimed in briefly on 30k..... the game. Lets take a look at what is being said.
First off, we are going to start off with our solid source here on Faeit 212. This is very reliable, but like always is still considered rumor.
via anonymous sources on Faeit 212
The new 30k game, it will be a game like Space Hulk, potentially limited run, will be released around Oct
Hastings has mentioned this will be a separate standalone game as well.
via Hastings previously
I heard that 30k HH would be a boxed standalone game (like execution force was) and that the plastics contained within it would go on to form part of a larger 30k range and would be released some time later as individual box sets/clampacks, I was told that rules would be in those boxes, but that some boxes would contain rules for 30k AND 40k (and these boxes have BOTH logos on - yes there is a new 30k logo) so I assume it will be using a different ruleset to 40k (as there would be no point having rules for both systems in boxes if they were both the same). I was also told the plastic assassins would get clampack releases later and be released as part of the main 40k range..... as the box set is pretty much still quite widely available I don't expect this to be soon, although I never had a timeframe in the first case.