Choujin Heiki Zeroigar (1997)

Choujin Heiki Zeroigar is an action shooter. The player controls Zeroigar as a plane and as a robot. The player is awarded experience points, depending on his performance during a stage. The Galactic Emperor Zemu is conquering one planet after the other, planning to expand his empire to the known limits of the galaxy. The reason for his success are huge robots who fight in his armies, developed with the technology invented by the genius scientist Dr. Lulu. But the doctor understands herself that her inventions have caused misery and destruction to other nations. She runs away, taking design plans for the giant robots with her. She arrives on the Earth (Japan, to be exact) shortly after World War II, and with the help of local scientists, develops a powerful robot, that alone can protect Earth from Zemu's attacks: Super God Trooper Zeroigar! Zeroigar is the only shooter for the PC-FX system, continuing the legacy of vertically scrolling shooters from the PC Engine (TurboGrafx) era. The player controls Zeroigar as a plane and as a robot (for boss battles). As in most shooters, power-ups appear frequently. Every level starts with the default weapon, which can be enhanced with these power-ups. Secondary weapons (bombs, torpedoes, etc.) can also be found. A somewhat unusual feature of "Zeroigar" is its leveling-up system. The player is awarded experience points, depending on his performance during a stage. After completing a stage (or after a Game Over screen), the player is able to use those points to increase Zeroigar's parameters (health, defense, weapon power, etc.). The player is given unlimited continues, but he has to begin the level from the first screen each time. Anime-style movies advance the story between levels.

Storyline

Star Calendar Year Beta-28 The galaxy suffers under the conquest of the mighty Celestial Empire. Planets overtaken by this empire face total destruction at the hands seven super-weapons invented by genius Imperial scientists. Galactic civilizations have lost the will to fight... Hope has all but vanished in the universe... However, someone has finally taken a stand to end the reign of violence. Her name is Luru, and she is one of the scientists working for the Empire. She has taken her designs for what was supposed to be the eighth and ultimate super-weapon, and hatched a plan to escape from the Empire's sight. However, the Imperial High Commander quickly learned of her plan, and informed Emperor Zemu, who ordered Luru’s immediate capture. The one to execute that order would be none other than Luru's brother, Lunoa. He attempted to convince Luru to return, but perhaps out of love for his sister, he didn't act fast enough to stop her when she refused. He chased Luru in the Rubel, one of the seven super-weapons of which he himself is the pilot. However, Luru managed to warp far away to a place that no one, not even the Emperor, could ever imagine... ...to Japan in 1945, just days after the end of the Second World War.