Nightmare Academy #3: Monster War by Dean Lorey

Charlie is in big trouble

Dangeroos, Mimics, Netherstalkers, and worse are everywhere, and the danger to our world has never been greater. The Named have succeeded in summoning the Queen of Nightmares, a villain so terrible that only one person can stop her—Charlie Benjamin, armed with the Sword of Sacrifice. But Charlie can't get the fabled sword without the help of his friends Theodore, Violet, and Brooke—and the sacrifice it demands from them is even more horrifying than a roomful of Ravenous Sticky-Spitters. . . .