How does the curse of the Hornsent work?
There seem to be really conflicting ideas about this. Some people say that the curse was the origin of the Omens, others say it cursed Marika's bloodline specifically with being Omens. Some people say that it was in retaliation for her and Messmer's genocide but I feel like that doesn't make sense seeing as Mohg and Morgott were already born at that point.
If I had to guess I'd say it was a curse upon her for becoming a god and then abandoning/betraying them, and the curse specifically was that all of her children would end up with something wrong with them (which is true for all of her and Radagon's children. Godwyn dies only in soul and Ranni in body, Messmer and Rykard with their snakes, the Omen Twins, Radahn ends up rotted and Malenia is born that way, Miquella is cursed with eternal youth and Melina ends burnt and bodiless).
I think it makes the most sense that they cursed her and maybe before that Godfrey killed a bunch, and then her kids were born all funky so she sent Messmer to finish the job.