Skulduggery Pleasant: Dead or alive - Derek Landy (Skulduggery Pleasant #14)

Pedestrians passed in front of the car. One of them stopped, patting the pockets of his long coat. 

He turned and brought up an assault rifle.

Then the whole world was the roar of gunfire and the sound of the dashboard being chewed up. Valkyrie's ears were ringing so much it took her a moment to register that the gunfire had stopped.

He was reloading.

Billions of lives will be wiped away in a final, desperate search for the Child of the Faceless Ones, she who is destined to bring about the return of humankind's ancient overlords.

To prevent this, Skulduggery Pleasant and Valkyrie Cain have one last terrible option: the assassination of Damocles Creed. With protests stirring in the magical city of Roarhaven, Valkyrie must decide who she wants to be: the hero who risks everything for a noble ideal, or the killer who sacrifices her own soul for the fate of humanity.