When I was work in Light Games Team Company my main goal was a creation of 2D Arcade game. That was a Space Shooter.
"Space Shooter" is a game that belongs to the genre "Shoot`em up" or "Run and Shoot". In this game, you play as a spaceshutle that moves forward, fires multiple enemies and at the same time avoides the bullets of enemy spaceships. It has a points scoring system that depends on the number of enemies killed. To set a new record, a you as a player must score a certain number of points that will be higher than the previous score. Win condition in this game does not exist, because only new records can be set many times.
To survive, the player must respond to enemy attacks and the objects that are directed at him, as well as remember the sequence of enemy attacks.