The Halo franchise is owned by Microsoft, and includes nearly a dozen games. The main games are first-person-shooters, but some are strategy games. They are available on the Xbox and personal computer.
Halo is a first-person-shooter video game and book series set in the midst of an interstellar war between Humanity and a theocratic alien race called "the covenant". It is set in the 2550's, and the first game opens with Humanity on the verge of extinction. It is only released on the P.C. and the Xbox.
The first game, Halo: Combat Evolved opens with the UNSC (United Nations Space Command) vessel The Pillar of Autumn floating in space near a large ring-like structure. The Autumn had just escaped the destruction of Humanities' last military stronghold (aside from earth), and is heavily damaged.The ship is ambushed by a fleet of Covenant Vessels, and the captain decides to land on the ring. Spartan John-117, or "the Master Chief" is a genetically modified super soldier. He is wearing bionic armor, which gives him shielding and the strength of 20 men. He escapes the Autumn aboard a lifeboat, and lands on the ring. Throughout the game, he continues to fight the covenant and rescue surviving Marines, and even starts to form a functional resistance with the help of Cortana, an AI (Artificial Intelligence- a sentient computer program). The Master Chief learns that the ring, "Halo", is part of the Covenant's religion. They believe that it will carry them into the afterlife. In reality, the Chief discovers, it is one of seven rings that will destroy all life in the galaxy. Unfortunately, he soon finds the motivation for their construction: an ancient parasite known as the "Flood". They latch onto a living host and kill it. They then proceed to mutate the body and use its bio matter to infect new hosts. The Chief then fights through hordes of Flood and Covenant, eventually destroying the ring. The rest of the games fallow him as he eventually destroys both the flood and the covenant, saving humanity.
At first, one may think that Halo is very atheist (due to the enemy being a theocracy, and being blindly driven by their faith), but it is actually surprisingly Christian. The Covenant are based on Islam, and act more like radical Muslims than the Atheist view of the "idiotic Christian". Furthermore, The Master Chief's military designation, "John 117" is a reference to a bible verse: John 1:17 "For the law was given through Moses; grace and truth came through Jesus Christ."
The struggle of The Master Chief to save humanity from the covenant could be compared to the fight of the right wing to save America from the radical ISIS.
The game does not come without morality issues, but they are surprisingly Moral.
Almost all enemies in the Halo games are Aliens, so the player never needs to harm another human being. All human characters are savable (it is possible to have zero human casualties). The player Is able to kill Marines, although they will usually try to kill the player if this is attempted.
John 117 is one of 33 "Spartans", genetically augmented super soldiers. They were kidnapped at 6 years old and brought to a training facility where they were trained as soldiers, and eventually modified. The group originally numbered in the hundreds, but most died on the operating table.
Despite the bleak and immoral actions, the game does not try to justify it. In fact, the characters are constantly criticizing the doctors who kidnapped the children, and the in-game government sentences them to life in prison. The Spartans themselves, however, are at peace with the knowledge that Mankind would have fallen decades before without them.