De la Cruz, Melissa, 1971- Blue Bloods novel #9

Sequel to: After life

When a new girl named Eoife arrives at Duchesne Academy, Schuyler discovers she is another Max Force ally as they team up to solve the theory of chaos magic, fight off the enemy, and put an end to the war between heaven and hell

After defeating Lucifer and saving the world, Schuyler Van Allen woke up in an entirely different reality... and has to do it all over again. Only this time it seems she'll have to do it alone. When Eoife shows up at Duchesne Academy, Schuyler at first thinks she must be yet another enemy. But Eoife is here to help: she's a member of an ages old secret society of heroes called the Palladins, and she has friends-- lots of them. United with another unlikely ally in Max Force, the group might just have a fighting chance-- if they can find and rescue Jack, get Max's Blue Blood powers back, solve the theory of chaos magic and take down a friend turned foe. Oh, and fight off an army of Silver Bloods and otherworldly monsters led by the devil himself. -- adapted from jacket