The premise of Skychase is very simple. Two planes battle it out over a flat landscape. And that's it. If this sounds single-minded to you, then you've got the picture. It's a good time to worry when a game bends over backwards to make itself totally user-definable - it often proves to be an attempt to mask a lack of depth. This game gives you a lot to worry about.
Skychase is basically like the dogfighting bit from a flight sim, with every other aspect of the game removed (even the realism). This may sound like a good idea, but in reality it becomes tedious all too soon.
Still, I did find myself playing it for a good twenty minutes before it began to feel like a chore, and the two player mode is kind of fun.