I have been having this debate with my players for quite a while now. Can a SM suffer from blood loss? Can one die from it? How severe does it have to be? Please help

As per page 36, they don't unless attacked by a Warp Weapon. Why would you or your players think differently?

(It should be added that normal weapons do cause blood loss on the SM narratively . But blood loss in those game terms refers

to a state where an accumulating blood loss becomes so extreme that it turns life threatening. The "normal" blood loss, otoh, is

rolled into the wound damage of an attack from a game mechanic's perspective.)

Alex

Well the thing was, that A Space Marine, somehow, cut off his own arm with a swoop of a ChainAxe. (Please don't ask me how, As a GM it was just painful to see) Anyway, we had an argument about him suffering blood loss, as he has instantly cut off his own arm. Would that be severe enough?

Any blood loss of the amputation should be considered part of the initial damage of the attack.

Read page 17, Larraman's organ. You could split a marine in half and he wouldn't die from blood loss . Unless attacked by a Warp Weapon which apparently affect Larraman cells.

Alex

I see Thank you

Effectively marines will always bleed when cut, everyone bleeds and a marine are no exception. The organ though stops them suffering blood loss and continual loss of blood as it clots quick enough to stop it spurting out like a bad horror flick.

Personally I prefer the BC revision which simply lowers their chances of dying from Blood Loss, but in DW RAW, yes, marines are immune to Blood Loss mechanically.

One of the Ultramarine books has a Captain ventris I believe get his throat cut open. He put his hand up there for a few moments to slow the blood flow and a few moments later, the wound was all closed up.

Space Marine healing powers are the boss.

Well... Nobody is dying of blood loss any time soon haha