Valve’s Left 4 Dead has brought 4-player coop back from the dead, everyone (who was alive in the 90s) loves the original Rainbow Six, and people still buy XCOM and Jagged Alliance on Steam, so why not mix them up into a delicious game of soup.
I was playing the popular single-player Half-Life 2 mod CS:S Scifi the other day when it struck me that the only thing missing was coop. And boy how it was missing!
To quote from their website:
“Each mission is goal-oriented and non-linear and can be played and replayed using different tactics, options and strategies. CSS SCI FI includes an interactive mission hub and full Configuration Utility which players can use to select different styles of gameplay, ranging from extreme realism to gib-tastic gore…
Replay value sets CSS SCI FI apart from other single-player mods. Because the layout of each map is non-linear, there is never only one way to approach a particular target or goal. Players can work through each mission as many times as they like, discovering new features (including hidden secrets) and using new options from the configuration utility each time. Resources are distributed differently and enemies change their tactics with every play, making each mission a unique experience.”
This whole gameplay concept, perhaps most popularized by Hitman, Metal Gear Solid, and Crysis, has been dubbed Same Situation, Multiple Approach by some hardcore gamers I know. The fun in these games comes from iterating ones tactical approach to a situation until success is met; or just to try out different ways of completing a situation for the fun and difficulty of it.
The replayability inherent in the concept is essentially the same as that exploited by Left 4 Dead, except without the fancy Director AI to choose interesting spawn locations. Adding a better enemy and equipment placement system and a random scenario/map/objective generator would greatly increase the already fantastic replayability. CS:S Scifi also lets you change the ruleset in ways that make gameplay more replayable.
Adding stuff like detailed hardware and weapon restrictions, ability to tune the random map generator, and the frequency and type of enemies in detail would be great. Another way to add replayability would be to give players the option of saving and even completely customizing the output of the random map generator by hand detailing enemy spawns, weapon placements, and room/map layouts (with a simple WYSIWYG editor with limited functionality like the THPS2 map editor). Oh, and be able to share these with the community.
Classic squad-based tactical games like Rainbow Six or XCOM are premised around a similar replayability because of the breadth of tactical options available. CS:S Scifi, acknowledging the possibility of teamplay, even offers AI companions who travel with you but are largely useless. Adding a 4-player coop mode and making it the central gameplay focus would greatly enhance the fun factor, in my opinion. To help out with teamplay a tactical map that could be drawn on by players to give attack routes would also be useful.
Overall, I think you could make a killing by piggybacking on Valve’s success but with a very different gameplay format. Especially important is providing a variety of missions sizes – Left 4 Dead is a game that requires extended time investment to be fun, whereas a 5 minute mission game could be really fun as a change of format.