Adventure Two, Session Nine Recap

The party is in the middle of a massive battle with both members of an organization attempting to capture Teffa, and now an undead, mummified mind flayer...!
When last we left our party, Temerity had just, against her will and under the command of the voice in her head, opened the sarcophagus of Inhopthek. It turned out, however, not to be the ancient hero within the tomb, but rather his mortal enemy, the inhuman Xananlanthi Xanaloth. Brill Brall, upon examining the mummy, seemed to think the creature was actually an undead mind flayer!
Xanalanthi's first move was to go for Zelna, who he reeled in using his mind powers. Once in his grasp, he latched his facial tentacles onto her head and began sapping her vitality. It turns out he was attracted to her because SHE had the Rod of Ryktuss (not Vorliss). Vorliss, for his part, moved to rescue Zelna from the creature, taking damage from the party along the way. He managed, with the PC's (unintentional?) help, to free Zelna and pull her to relative safety. But the rod fell into Temerity's hands. She quickly passed it to Teffa, who ran upstairs with the rod, only to be intercepted by Faylin Harbole along the way. Faylin attempted to explain that he was Teffa's only chance at making it out alive, as only he could hold back the bounty hunters who had come for her. Teffa chose to ignore this and pushed ahead upstairs.
In reaction to this, Xanalanthi simply disappeared, either turning invisible or teleporting to a different spot.
Temerity and the others soon followed, with the tiefling managing to find an offensive position at the top of the stairs. When Faylin pursued and reached the top step, she blasted him with a "Thunder Wave," sending him spilling down the stairs. He landed hard on his neck, and is now either unconscious or dead.
Teffa cast an "Entaglement" spell on the opposite stairwell, which Vorliss was climbing. When the death knight reached the top, he simply dispelled the magical tangle of barbed weeds.
Once Vorliss was firmly on the second story, he attempted to parlay with Temerity, telling her he was the only one who could use the rod and summon help. It seemed as if he was attempting a "team up." Temerity retreated from him, but then Xanalanthi appeared right in her path, materializing out of thin air. The mind flayer suddenly went for her, using his mind traction ability to reel her in. Like Zelna before, he used his tentacles to sap her vitality. Trapped between a rock and a hard place, Teffa managed to get the rod from the creature, just as Vorliss attempted to engage him. Xanalanthi dropped the unconscious and dying Temerity and went after his new foes.
In the confusion, Vorliss grabbed the rod from Teffa and used it to attempt to wake the dead. The natural history exhibits of skeletal and stuffed animal remains (including a T Rex) began to stir.
Brill Brall made it to the second floor in time to help stabilize Temerity before she could expire, but was unable to help stop Xanalanthi as he grabbed the rod from the death knight. And now the evil mummy has one half of the Rod of Ryktuss...