Emma is taken to Xavier Institute for examination for her secondary mutation, while Hisako joined the group to continue training
In the original version, secondary mutations are called Damon-Hall Syndrome. In the English version it's an unknown virus.
Emma has a benign version of Damon-Hall Syndrome
If mutants afflicted with Damon-Hall syndrome are allowed to let their powers go out of control, their bodies will eventually overheat and petrify.