Originally reported by IGN, the add-on, titled "Heroes," will feature two new game modes and a patch that significantly overhauls parts of the game.
The first mode is called Survival, and it changes the traditional Resogun formula by giving you only one life. Each session, then, turns into a tense struggle to accumulate the highest possible score by surviving the longest, hence the name. The difficulty of having only one life is coupled with the addition of a day/night cycle into the game. The more days you complete, the higher your score, but the harder the enemies become.
The mode also changes the collection of humans from the original Resogun modes. In the base game, there are a set number of humans that can appear per level, and you must collect and take these humans to certain gathering points to increase your score. In Survival, however, humans appear much more frequently and without limit, and you only have to touch them to rack up points.
Finally, Housemarque is adding presentation improvements with Survival, from graphical enhancements to new sound effects and entirely new music.
Mikael Haveri from Housemarque has also revealed more detail about Demolition mode on the PlayStation Blog. In Demolition, your weapons are taken away and you become a "wrecking ball" that destroys enemies with explosions and collisions. Several power-ups alter the gameplay, as well.
The last part of the DLC, the patch, brings a ship editor and local co-op to Resogun, in addition to small tweaks and improvements. Housemarque has not detailed the editor or the local co-op yet.
Heroes will launch on June 23, and will cost $4.99. Housemarque also announced that it is developing more content for Resogun and has made a season pass available. The pass will cost you $7.99.
GameSpot thought that Resogun was great when it was released last fall. Keep your eyes on GameSpot for more about Heroes and Resogun's future DLC when it is revealed.