It was Yagi's way of confirming she's dead , or just some completely random reaction that was placed in the story for nothing
As I said, it's most likely Isley. He's been around since they started making Claymores. He can sense auras. In 7 years, someone can train to equal Galatea. What could they do with 70+ years.
but still, maybe the arm acted weird cuz for the eyes of the organization, ilena had to look like dead and whatever was that they did to fake it, her arm reacted too...
maybe, maybe not
i know its most likely that she is dead, but i liked her, so i wish she was still alive
I think it's Rafaela. Maybe Rafaela is also plotting some revenge against the Organization. Maybe deep inside her is a hidden anger against the Organization for making them a monster or something.
I think eramita (forgot how to spell it) he seemed quite affectionate to the claymores (well before they awakened) and wasn’t he the black cloak in charge of Miria as well as Galatea. His motive is probably that he doesn’t want to see anymore of his "children" awaken or something like that.
I think all he wanted by saying to Galatea "Think of it as a parent's concern for a child" was an excuse for spying on the semi-awakened... from the start thay were sent to a suicide mission.
Think Ermita was in charge of both Galatea and Miria. He could be a suspect although most favor Rubel, since he seems to be everywhere esp when something interesting is going on or the Org needs somebody. Both seem to have a habit of letting things slip out when talking to their charges.
Orsay (Teresa's handler) and Rado are dark horse candidates. Rimuto would be the least likely MIB to spill the beans since he's the head of the Org.
Then if not Rubel, which is high likely but too much predictable for Yagi's style, it can only be new character, and someone from the handlers or the council.
i think the collaborator is this one:
maybe galatea,she's always showing up and just watching.
Miria's informant was Rubel.
chapter 83 page 31,
chapter 84 pages 1-7, and
chapter 84 pages 22-31
chapter 84 page 28