Phobia

The evil Phobos has created 15 planets full of danger, each of them representing things humans commonly fear. The levels include ones based around spiders, snakes, dentists and similar, surely including something to scare anyone. To rescue the Galactic Emperor, you must negotiate all of these.

The action is mostly one-dimensional blasting, but with distinct sections of flying to a level, flying around it, and then navigating an underground cavern. A simultaneous 2-player mode exists to make things a little less daunting.