The way I see it now, we have two conflicting descriptions of what the spell does, but neither would cause the death of Tarquin.
Assuming "direct bloodline" means "-parents" and "-children", this would happen:Originally Posted by Darth V
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The people in red (including all of the omitted Draketooth clan) were all killed, and caused the death of the people in pink (who are either members of branching family paths, or people who "married" into the main branch), and then it would stop. The families of Penelope and the other people tricked by the Draketooth would not be wiped "to the last cousin", only a direct line of ascendency/descendancy would be killed. That, of course, contradicts:
This definition ignores the "direct" part, and says everyone "with the blood of the black dragon is killed". This means cousins and uncles/aunts of the ABD would be part of the first loop, and should be painted in red instead of pink. This would also mean most of the people in blue in the first chart are now in pink.Originally Posted by Guilty V
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However, this definition still wouldn't have killed Tarquin even if he had a child with Penelope. The second loop was targeted at Penelope, not the hypothetical child. Everyone who shared blood with her would be killed. And, as much as Tarquin would share blood with the kid, he'd still not share blood with her.