Casting a Long Shadow

Steps
I entered the Tower of Frozen Shadow expecting an immediate fight. I was instead greeted by a coldain strike force who had invaded earlier in an attempt to defeat Tserrina. They hit a road block, however, when attempting to clear out the first floor. Aware of their imminent failure, they asked me to pick up their slack and defeat each floor's master. Once I've done that, I should be able to access the eighth and final floor, where Tserrina is waiting. I must kill her!


 * 1) Defeat Xalgoti on the First Floor: Submergence.
 * 2) I must defeat the master of each floor in the tower.
 * Defeat Spectral Librarian Emiida on the Second Floor: The Frozen Library.
 * Defeat Vethilot The Young on the Third Floor: The Shadow Barracks.
 * Defeat Cara Omica on the Fourth Floor: Darkness Rising.
 * Defeat the Manifestation of Tserrina's Rage on the Fifth Floor: Bride's Scorn.
 * Defeat VhalSera on the Sixth Floor: Stewardship of VhalSera.
 * Defeat Necretia Widowmaker on the Seventh Floor: The Palindrome.
 * 1) All that remains is Tserrina herself. I should return to the first floor and speak with General Coldhammer about an attack plan.
 * 2) Confront Tserrina. Use the scroll the General gave you to weaken her.
 * What, you let her escape?