A City Sleeps is a horizontally scrolling shooter video game developed by Harmonix for Microsoft Windows and Mac OS X on October 16, 2014.

[1][4] In addition to her own abilities, Poe has a trio of "ghosts" that accompany her and that can be attached to special nodes located on the levels.

Each ghost has a unique ability: one can heal Poe, another can shoot its own bullets, and the third can drain health from enemies trapped nearby.

The player can swap ghosts and nodes at any time, though foes will continue to fire on Poe during this process.

[2] A City Sleeps was developed by a part of Harmonix' team that worked on their first-person music-based shooter, Chroma.