Valve will be celebrating the first birthday of Day of Defeat : Source on 28 June and will be offering a "free map pack" to anyone who owns a copy of the WWII game. According to Valve, the map pack will introduce a new gameplay style - "Detonation" - as well as two new missions (Jagd and Colmar).
The devloper said that there are also "gameplay enhancements," such as "such as spawn clip adjustments, improved hit location detection, and weapon balancing."
The Colmar mission is set in Northern France and is designed to introduces Day of Defeat’s "Detonation" style of gameplay. Marred with cold weather conditions, Colmar’s Detonation objectives drive successful teams to attack target areas in unison, Valve said.
Screenshot from the Colmar mission
Jagd - which translates into "Hunt" is described to challenge teams to a more advanced urban Detonation mission, "one that most be completed in a limited amount of time and is therefore unforgiving to unorganized offensive attacks," according to Valve.