Mystique told them that she had been lonely and wanted to join the X-Men.

He traveled to the 20th century and joined the X-Men, a team he knew only as legends.

Mystique tells them that she had been lonely and wants to join the X-Men.

But she eventually missed teaching and decided to join the X-Men.

Though he ultimately does not join the X-Men, he becomes allies with them.

He joined the X-Men, becoming the first member of a secondary team to "graduate".

Sam later officially accepts an invitation to join the X-Men.

At first, it seemed like there was no chance of Kitty being allowed to attend the school and join the X-Men.

Together, the two escaped and joined the X-Men afterward.

Kitty soon rebels against this and joins the X-Men as their youngest member.