Essentially the first Alien movies turned into a top-down shooter and filled with atmosphere.
As the excellent history provided with the game tells, Team17 (who made the Worms games) once made a creepy, atmospheric and quite difficult game called Alien Breed. The game was based on the film Aliens and this is an updated, but still authentic remake of that game.
The idea is that there are aliens attacking. You need to scour the corridors for items, such as keys and ammo, in order to make it to an elevator located on each level. The aliens will continue to breed off screen and come to attack you, so time is of the essence while also conserving your limited ammunition.
The graphics in this offering are very high quality and will remind any seasoned player of the early '90's graphics style, such as Alien Carnage (the original from Apogee) albeit in a slightly darker tone.
To put it simply, this is a great title you should not miss out on. Alien Breed Obliteration comes very highly recommended.