The 6th edition rulebook introduced , Flyers , Fortifications , and a completely reworked Psychic Phase . Space Marines, the poster children of 40k, needed a codex that could handle the new aerial and psychic threats. They got it with this release.
Prior to this codex, variant Chapters (Iron Hands, Salamanders, etc.) were often restricted to specific characters or minor trait rules. The 6th Edition codex formalized this into . Players chose a Chapter upon army creation, granting specific universal special rules to the entire force: 6th Edition Space Marine Codex Pdf
: This edition saw the Black Templars folded into the main Space Marine codex for the first time, though they retained unique units like Crusader Squads and the Emperor’s Champion . New Units : The 6th edition rulebook introduced , Flyers ,