Originally posted by Release Announcement:

After almost 7 years after it's inception we finally got the chance to finish one of our most beloved projects, with our best version yet. This mod has been through countless iterations some with some ingenious and downright crazy implementations, everything from flowgraph simulated AI to having the editor communicate with a dedicated server.

But finally with some very clever code we have managed to get the default Singleplayer AI working in multiplayer, it is then up to us to network all of the movement, animations, weapons and mission scripts. This is quite a large undertaking which is why there is only one campaign level in the first build and even that is still a WIP.

Originally posted by SC:

One of the things we have been hard at work on is a complete rework of the Half-Life 1 co-op conversion. The new conversion will be much closer to the original Half-Life experience, with fewer Sven Co-op specific additions that ruined the original atmosphere of Half-Life. Many of the levels have also been merged, which allows for far less frequent map loading sequences, and player health and loadouts will be carried over between levels. The Half-Life co-op campaign has also been chosen to showcase a new major addition to the game: Survival Mode. When Survival mode is active, players who die will be respawned as 'observers', who observe the game in progress and will only be able to return once the living players have reached a checkpoint or until someone revives them. The result is an experience much more similar to Half-Life Singleplayer, where players can lose the level and must reload to try again. A video demonstrating Survival Mode and the checkpoint system can be see below.