688(I) Hunter/Killer, the most realistic submarine simulation ever developed for PC. Master the sonar and weapons control systems, learn to develop real target situations and outfit your boat with the latest advanced weaponry. Then use your skills to complete the tour of duty and earn your dolphins to become a true submariner.
Over 12 detailed operating stations: Control all aspects of submarine warfare, including the sonar suite, fire control, helm and target motion analysis
Multiplayer Warfare: Seek and Destroy up to 8 players over the internet or LAN
Real-life situations: Conduct detailed training and single missions, plus a full campaign based on political analysis from real world situations
Full 3D Technology: Full 3D technology allows for multiple camera views and accurate 3D models of over 20 different naval weapons platforms
windows Minimum
OS: Windows 2000/XP/7
Processor: Pentium III
Memory: 256MB RAM
Graphics: 32MB video card (Nvidia Geforce or ATI Radeon)
Storage: 1.5G Hard drive space
To activate the game, you need a Steam Account
Login or register at the official Steam Website and download Steam client
Install and start application, login with your Account name and Password
Click the Games Menu.
Choose Activate a Product on Steam...
Follow the onscreen instructions to complete the process
After the successful code verification, go to the "MY GAMES" tab and start downloading.
News & Updates
2026-04-21
From Wishlist to Courtroom: The Steam Lawsuits Explained
There have been numerous Steam court case lawsuits throughout the years and ever since the start of the year they have made the pile even bigger! We decided to check out some of the latest accusations against the popular gaming platform as well as go through some of the previous cases that caused a stir of Valve legal issues in the past! Gabe Newell and Valve have definitely not been strangers to the court system…
As you probably know, in a huge variety of game titles there are usually a lot of mainline task objectives, but very often there are multiple side quests that would advance you further in the gameplay. This is exactly why we decided to run a Side Quest promotion on our YUPLAY site. In order to participate in it you have to make an order over 20€ between 17.04.2026 18:10 CET and 20.04.2026 02:00 CET, and you will get a 1€ voucher for next purchase…