The familiars are all broken so I gave her Imp the same familiar bonus as a Compsognathus or Greensting Scorpion (+4 initiative). He spends most of his time shape-shifted into the form of a Raven. He can communicate telepathically within 50 feet as well, and also Commune with the lower planes to offer guidance to his master. Before combat ideally, Semnane will haste her party. This is particularly important for Alabaster. Then she will set to work debuffing. Her slumber hex (DC 22) can put down martial classes effectively. If the enemy is grouped up and appears to be largely melee, Black Tentacles is a good one. Enervation and Ray of Exhaustion for casters and dex builds. On defense, Sleet Storm or Obscuring Mist can protect against ranged attacks and the Flight Hex will effectively allow her to avoid melee attackers. If she gets a chance before combat, she may use Reduce Person on herself or Wand of Enlarge Person on a friend.