The new AM dex

[N1SB]

Yeah, there is a page of rules about how Astra Militarum units can be taken by Chaos, just highlighting them:

1. Faction Imperium becomes Chaos, <Regiment> becomes Renegade & Heretics.

2. A table/list of all the units you can take from the Imperium, which are many but not all, like for example you can only take the basic Baneblade, not the variants

3. And in that said list above, it tells you the book you are supposed to refer to for that unit entry. About half are from the old Imperium Index 2, like the Leman Russ

That last point is that what ought to be FAQ'd to avoid debate because the way it looks now, Renegade & Heretics lets Chaos armies take certain Imperium units AS THEY WERE in the Imperium Index 2, because it SPECIFICALLY refers to that (now outdated) document. It might have just been trying to be helpful at the time, like telling you where to look for the unit profile, but it also locks it down to just that version of the unit. This will affect things like how the Codex gives Leman Russes the Grinding Advance objective secured rule whereas the Index version didn't.

I myself believe it's meant to allow R&H to take the most updated versions of the units myself, but because of how it was written, I'm just going to wait until the FAQ comes out for those (like the Leman Russ's huge buff in its Codex incarnation). In the meantime, I'm using things that really haven't changed between the Index and the Codex (like the Wyvern), so I can avoid wasting time on a debate with my opponents.

UPDATE - so the FAQ came out Oct 22, 2017. No Grinding Advance for us sadly with Rules-As-Written.

FURTHER UPDATE - it is now mid-November 2017 and NEW FAQs and Designer Commentary ( https://whc-cdn.games-workshop.com/wp-content/uploads/2017/11/warhammer_40000_designers_commentary_en-1.pdf ) provides an argument to get the AM Codex version's Leman Russ in this flowchart:

Edited November 19, 2017 by Not 1 Step Backwards