Halo: First Strike is a sequel to Halo: Combat Evolved authored by Eric Nylund and taking place before the events of Halo 2. It was published in December 2003, after being written in a period of sixteen weeks. The novel, along with Halo: The Fall of Reach and Halo: The Flood, was reissued in 2010 by Tor Books, with the new version including some content updates.