Top-down shooter Alien Syndrome is modeled after the first Alien Syndrome video game, which was developed and published by Sega. The game’s events occur in the distant future, thousands of years from now; at this point, humanity has traveled to many different areas of the galaxy and established many colonies. One of these colonies, known as Seti-Alpha 5 (SAT5), has suddenly stopped communicating for unknown reasons, and it is your responsibility to travel to SAT5 and determine what caused the problem. Upon arriving, you will come face to face with the alien syndrome, a force that has the potential to transform both humans and machines into dangerous aliens. The events in this sequel take place approximately one hundred years after those in the first Alien Syndrome.
You can select one of several characters and a character specialty when the game starts. These character specialties include demolitions expert, firebugs, seals, tanks, and sharpshooters. Your initial character stats will be determined by the specialization you choose; as you progress through the game and achieve levels, you will receive experience points to increase your character’s attributes. Your character’s range of close combat accuracy, speed, healing power, resilience to fire and radiation, armor strength, and other details are partially determined by the character’s statistics.
The action is seen from above, much like in the classic version of the game. It would be best if you cleared out the countless alien invaders hiding within the SAT5’s many rooms and corridors. SAT5 contains a large number of both. You will frequently be given mission goals that need to be performed to progress. The levels are littered with hidden caches of supplementary arms and ammunition and various other valuable objects. Your player character has a finite supply of energy, and if all of that energy is depleted, you will have to start the level again at the most recent checkpoint you passed.