Kingdom of The Wicked (Skulduggery Pleasant Book 7), Derek Landy

He’s dead. She’s deadly. The bad guys don’t stand a chance.

The seventh book in the bestselling Skulduggery Pleasant series. Magic is a disease. Across the land, normal people are suddenly developing wild and unstable powers.

Wielding the magic of the gods, they’re set to tear the city apart, unless someone stands up to them. For Skulduggery and Valkyrie, it’s going to be another one of those days.