While the dispute with Azure works its way through the morass of litigation. For want of something to play, I discovered more than a few who are back to playing Alien Swarm: Reactive Drop.
Alien Swarm: Reactive Drop is free to play on Steam and it is an isomorphic coop action shooter. Reactive Drop includes Jacob’s Ladder along with the best of the popular third party expansions. All of the new campaigns are multimap so that there is lots of gameplay available.
Reactive Drop has more alien creatures to fight. These are seen on the new campaigns which were assembled over the years since the original game was released. This makes it easier to make the achievements for 25,000 and 100,000 kills.
Levels are slower too. Making the 25,000 achievement is easily done before the 7th medallion is reached. It can take well over 70 hours of gameplay to get all of the mediallians. I still think the game maps would have been better used for the first person mode which would have made the coop action game far more playable. I have played a lot of shooters, some excellent and some are garbage. Many are a surprise and others are not well designed.
The challenge mode with the ultra hard level makes the game more difficult even for the most experienced groups. Halo: Combat Evolved is still a great example of attention to detail. To this day the game is a great example of a success. More recently a person made a FPS with the name Doomed in respect to the classic game. Unlike Doom, Doomed has multiple levels and stairs but it also has limited ability to select weapons.