Schiller was studying David Haller's medical history.
Know yourself and your enemy, and you will never be defeated. As a ceiling-level Mutant, David's mental world was bound to be extremely dangerous. Going in unprepared would be far too risky, so Schiller needed to conduct a thorough investigation first.
Most of what he knew about Legion came from the comics, and Legion's background was not particularly complicated. It could be called one of Professor X's mistakes from his early years.
When Charles was young, he had joined a medical team in the Haifa region. There, he first met Magneto and also got to know an Israeli woman. Charles saved her, and the two fell in love.
A fleeting romance did not last long. They soon parted ways, but the woman was pregnant with Charles's child and never told him. After giving birth, she became Israel's ambassador to Britain, and the child went to Britain with her.
Later, mother and son formed a family with another man, Legion's adoptive father, Daniel.
The family of three encountered a terrorist attack in Paris. The terrorists killed Legion's adoptive father right in front of him. From then on, Legion went mad. His psychic abilities erupted completely, absorbing the personalities of the terrorists he killed, and things spiraled out of control from there.
Unable to control his powers, his mother handed him over to a female scientist at a Mutant Research Center on an island. But clearly, he did not receive good care—or rather, no one had the ability to care for him under those circumstances. His condition grew worse and worse.
Schiller learned what happened afterward from David's own account.
Because of the development of the Andromeda galaxy, Mutants were gradually running short on manpower. As mentioned before, the vast majority of Mutants were not