Crisis Core features many characters from the main game including Cloud, Tifa, Sephiroth and Aeries. The main story is focused on Zack and the Shinra Company with Zack trying to become a first class soldier just like his leader Angeal. At the time and throughout all of the FF7 series cloud is just a low level soldier who never makes it to SOLDIER. The story also explains that Sephiroth is not the only one winged angel in the series but there are others. Somehow they are all able to fly fine with just one wing.
Crisis Core is an Action Adventure game that is unlike the first game. Instead of moving from one place to the other gamers are given missions and sent to a certain place.