X-COM: Terror From the Deep

X-COM: Terror From the Deep is a strategy game, the second installment in the X-COM series and a sequel to X-COM: UFO Defense that moves action from the outer space into the Earth’s oceans. The story unexpectedly references to Lovecraft’s novels, as you fight aliens that want to reawaken their unstoppable leader who slept under the sea for hundreds of years.
The gameplay is divided into two parts: on the one hand, you built bases, develop your technology and upgrade the squad. On the other hand, you fight aliens during turn-based battles. As the game is set underwater, your weaponry is limited and you have to study new technologies to produce and improve it. Unlike in the previous title, in Terror From the Deep you can use melee combat along with guns and special devices.
The game features various missions with different goals. Some of them include fights on several locations, the others are terror missions on huge map layouts.