Tie in on why Beast had left the X-Men
After being druged by Kraven, Beast lost his mind and in an access of fury gets bersek and almost kill Raven. It would have happened if the X-Men doesn't stop him. After that the Beast left the X-Men for real,
It's really a needed tie in, because in the current title X-Men (or Uncanny X-Men) it wasn't never really explained why he had left the team.