Sergeant Duffy and the Kidnapped Scientist

Sergeant Duffy & the Kidnapped Scientist is not a good game. It's definitely made by someone who was experimenting with game development, perhaps for the first time. However it is a game that people would likely remember playing once they downloaded it, and it does offer some variety, so it's included here. Your mission is to rescue the kidnapped scientist Dr Jones. First you fly through a vertically scrolling stage avoiding obstacles, then jump through a spike-strewn cavern to rescue the doctor. Then the game ends.