Vertical Force is a vertically-scrolling shooter, with two layers (to utilize the 3-D features of the system) for Nintendo's Virtual Boy video game system. It was developed by Hudson Soft and released in December 1995.
Just like in most vertical shoot 'em ups, you control a ship whose purpose is to shoot any enemy that enters the screen. Collecting powerups will change the weapon used. The main innovation in this game lies in its use for the Virtual Boy system where, by pressing a button, the ship can move into the foreground to avoid or shoot enemies or collect powerups that lie on the ground below. Some boss enemies can only be destroyedavoided by cycling between the two fields occasionally.
An additional gameplay element that is fairly unique to Vertical Force is the ability to use "drones"; AI-controlled smaller spaceships that assist the player's starfighter. The game has a high-score board, but no battery-powered memory with which to save those scores, so they are lost when the player turns off the Virtual Boy unit. However, some players record their scores and post them on the internet, making a kind of virtual high score board