Back to the Future Part II & III

Back to the Future Part II and III is a 1990 2D platformer video game by Beam Software for the the NES. The game is based on the two movies of the same name, and is one of many video game adaptations of the film for the NES.

Gameplay
The game starts off in Part II and then proceeds to Part III. The objectives and gameplay are as follows: The player is given 10 lives at the start. When he loses all his lives, he has the option to continue playing at the place where he lost his last life.
 * Part II: Marty McFly must collect 30 artifacts from three different time periods that were scattered all around Hill Valley and purposely misplaced by Biff Tannen to keep Marty from getting his hands on the sports almanac. Gameplay is similar to a Super Mario Bros. game in that Marty must jump across platforms and avoid or shoot various creatures he comes across. Occasionally Biff Tannen will appear and attack him, either on foot or on a hoverboard. To jump from one time period to another, Marty must collect enough power cells in order to power up the DeLorean to make the jump. However, with each time jump Marty makes, he leaves behind a time clone that he must avoid or else it will cost him a life. When he enters a place where an artifact is located, he must complete a mini-game in order to get it. Then Marty must find the place in time and in Hill Valley where the artifact truly belongs. When all 30 artifacts are found, the sports almanac is now burned, and all is well...until Marty finds out Doc Brown is in 1875!!!
 * Part III: Marty must now collect 10 artifacts in the Old West version of Hill Valley and return them to their proper places. Gameplay is similar to Part II, except that there is no jumping around in time to do. Successful completion will bring Marty and Doc back home to 1985.

Story
Marty McFly's time travel adventures continue as he confronts Biff Tannen and his relatives in four different time periods, as he did in the movies. One of those periods is a messed-up 1985, in which Biff of 1955 is given a sports almanac from the future by Biff of 2015, and uses it to amass a fortune where he literally bought Hill Valley and turned it into his personal kingdom. Marty must get the sports almanac away from Biff of 1955 before he uses it, and then must go back to the time of the Old West to rescue Doc Brown from an untimely death at the hands of Buford "Mag Dog" Tannen.