On the eve of battle, the Blood Angels kneel in prayer and their thoughts turn to their Primarch. Some are overcome by the gene-memory of their Primarch's violent death and succumb to the Black Rage. To represent this, at the start of a battle, before the armies are deployed, you must determine how many warriors in your army have been infused with the Black Rage and joined the Death Company.
For each of the squads listed below, roll a D6 at the start of the battle. On a 1, 2 or 3 the squad fights normally. On a 4 or 5, one model from the squad becomes a Death Company Space Marine (your choice). On a 6 one of the models in the unit joins the Death Company and you must roll again (it is possible for two or more models from the same unit to join the Death Company if you roll successive 6s). If you have insufficient models to represent every Blood Angel who joins the Death Company, any excess models are simply lost.
Honour Guard; Terminator squad; Terminator Assault squad; Veteran squad; Veteran Assault squad; Tactical squad; Scout squad; Assault squad; Bike squadron; Scout Bike squadron; and Devastator squad. (Note that when a unit joins the Death Company its equipment is replaced with those in the Death Company army list entry).
All Death Company Space Marines fight as one unit. If you have a Chaplain in your army, then extra Death Company Space Marines join the Death Company accompanying him.
If you roll 4+ for a squad led by a Veteran Sergeant, he may also join the Death Company. He may be armed with a power weapon or power fist as noted in the Death Company army list entry.
Errata — Chapter Approved: Codex: Blood Angels Q&A (v1.0): When you roll a 4+ for a squad led by a Veteran Sergeant and choose to take him into the Death Company, this happens instead of picking another member of the squad, not in addition to one other member joining.