6. Halo 3
The incredibly popular series caps off it’s main trilogy, and does so in style. The armored soldier Master Chief fights to end the war between humans and the alien Covenant once and for all.
Andrew Ryan invests his money in creating an underwater city called Rapture. Rapture resides in international waters, and is not confined by petty laws, religions, or capitalism. Only great thinkers, scientists, and artists are allowed to live there. Due to the ethical freedom, genetic science gets an unchecked boost, resulting in powerful and crazy junkies, evil little girls, and nearly invincible monster bodyguards.