Originally Posted by
Perversor
I think you are dragging too much the lore in order to find something special, i often found that small short snippets of history or actions added to the lore seems to provide a lot of more interesting paths.
As example i play a devastated Craftworld where Wraiths are so common that unlike Iyanden and other craftworlds fielding them it's not a taboo but more a matter of proud. (warriors dedicated so much to protect their kind that choose to remain ever vigilant)
This craftworld has developed a special kind of attunement to the spirit stones and living warriors often join with other deceased souls of their infinity circuit and bond to carry them as guides to the battlefield.
This makes a pseudo exarch effect and the living one can tap into the memories and expertise of the deceased one allowing fresh warriors show the expertise of centuries hardened veterans.
side effects: if the warrior dies and is lucky both souls will be contained within the stone, otherwise the most oftenly is the strongest soul *melds* with the weaker devouring that warriors essence in a similar way as slaanesh may do, in some situatios long expositions to a *binded* deceased warrior soul can make the living eldar to take the shape and memories of the deceased ones thus slowly allowing them to reborn in exchange of themselves in similar way as Lucius does.