Board Thread:Manga/@comment-34172004-20190210143147/@comment-37687990-20200620051458

VERY late reply, but now that the full story of Ymir is out there, I don't think it was even mentioned that Ymir was an eldian. She was just a person who got captured and made a slave to be forced to work for the Eldian empire. She came into contact with the source of organic matter, yeah, then she had kids with the king, 'WHO WAS ELDIAN. Once she died and her remains were eaten by her children, WHO WERE ELDIAN', then that'd also make their descendants Eldian, which explains the Eldians being connected to the coordinate from Ymir.

(TLDR) So basically, because Ymir, possessing the coordinate, mingled with the Eldian king with her power eventually getting passed to her Eldian kids when she got eaten, their descendants in turn became connected to that very coordinate, hence the reason why Eldians able to become titans. I don't know if you've figured this out already, but I'm just putting it out there. Have a nice dayyy ^><^