Asuka & Asuka

Earth is invaded by a force called the Galaxy Highters in 1996, which was set in the future seen from the game's release in 1989. With their abilities in space time manipulation, the Galaxy Highters are able to invade several time lines in Earth’s history and occupy each one simultaneously. In order to stop them, Earth’s militaries design the "Flying Bird" (or "Asuka" in Japanese), a jet fighter capable of time travel, enabling it to fly into occupied time lines.

Asuka & Asuka is a vertically scrolling shooter in which each stage represents a certain time zone and has its own set of enemies in the air and on the ground. The first stage is a modern day port city with futuristic enemies, the second is a prehistoric landscape with dinosaurs shooting fireballs at your ship, etc.