Trouble Shooter

Trouble Shooter known as Battle Mania in Japan is a shoot 'em up game designed by Vic Tokai for the Sega Genesis released in 1991.

Plot
The game stars teenage sisters Madison(Mania in Japan) and Crystal(Maria in Japan) as they set out to rescue the kidnapped Prince Eldon who has been taken hostage by the criminal organization Black Ball.

Madison is the light hearted one whilst Crystal is the more serious individual.

The game has a comedic tone to it, with fourth wall gags including a credit roll interruption and the villain noting the amount of levels they've fought one another.

Gameplay
Despite there being two characters, the player actually plays as both Madison and Crystal at the same time through the majority of the levels, although as the player largely controls Madison, Crystal doesn't take damage from enemy fire. There are times when only Madison is playable or the player will be controlling Madison, Crystal AND the Prince simultaneously, with Crystal following Madison's movement back to back and the Prince travelling inverse of the direction the sisters go.

At the beginning the player is asked to pick from a variety of engines or power boosters, each of which give different ammunition to the girls. Once selected, the player is thrown into the side scrolling shoot em up gameplay.

Madison and Crystal have rocket boosters strapped to their backs and as such are airborne. The player must guide them through the level avoiding enemy projectiles whilst firing their own. The girl's bullets can neutralise enemy fire when shot at. Crystal will cover the rear, whilst Madison shoots opponents from the front. Crystal can be turned around in order to provide double the firepower in one direction.

Like many shoot em ups, there are a variety of unique weapons that the girls can use to upgrade their arsenal including giant laser beams that shoot vertically down, additional blaster drones to give them extra firepower, gigantic energy projectiles that rotate around the two of them and lightning bolts that rain down on enemies.

After traveling through a level the player will be required to defeat a boss at the end.

Trivia

 * Madison and Crystal/Mania and Maria both appear in Segagaga as part of the final stand against Dogma.
 * The game was heavily influenced by Dirty Pair.