The best part was when Cassandra Nova couldn't affect Jean's mind, even when she put down her defenses. Nova tried to tear apart her mind but couldn't do anything, then Nova attacked when Jean's mind was over stretched and undefended but couldn't do anything and had to attack Rachel instead (despite talking about how she was going to use the opportunity to take out Jean directly).
Honestly after seen this Jean Grey, this new Marvel Girl as the writer pretends us to call her, is a downgrade.