Simply put: This is the greatest modern submarine simulator ever. This game is not for most people, because it is pretty hardcore realistic. The playable submarines are: Akula and Akula Improved, 688(i) Los Angeles Class, Kilo and Kilo Improved. (They also make a MH-60 Seahawk, P-3c patrol plane, and Oliver-Hazard Perry frigate playable, but those aren't nearly as fun or polished) The level of depth they went through to make this as realistic as they could is breathtaking. Going through Sonar to find and classify vessels feels very rewarding. Once classified, you determine the speed through the Demon waterfall. After that, you go to the TMA (Target Motion Analysis) station to put in all the info to fire a weapon at it. All this takes time and a lot of effort, as you have to remain silent yourself because the AI is doing the same thing. If you feel overwhelmed by all this, you can put on auto crew on almost every station, so you don't need to do everything yourself, especially if you're bad at it. (Like me at TMA.) The campaign is very hard, at least for me. But you can train up on quick missions which involve you sinking 1-3 vessels depending on the difficulty you choose. And there is a ten-digit seed generator which makes quick missions infinitely re-playable. Overall, I would give this game a great thumbs up and 10/10 rating. [At the time of this review, I have 37 hours on record.]

THIS GAME DOES NOT WORK IN WINDOWS 8. THE DEVEL0PER HAS CONFIRMED IT WILL NOT RELEASE A PATCH TO UPDATE THE GAME. DO NOT BUY IF YOU USE WINDOWS 8. If you have an older version of windows this is a good game.

do not get this if you have winows 8 or better. it doesnt run and the company "doent support" this game any more.

Awesome simulation for modern naval warfare geeks.
Technical and immersive, endlessly replayable with the random quick missions and many player made scenarios.
Best with Reinforce Alert (RA) mod.

If you have windows 8 or higher, then you might as well say that the devs can throw a F*** party and only invite themselves. I am just lucky I got this on sale. I only waisted 4 bucks!