Simplistic game where you use keys O & P to navigate a spacecraft through a rather dense 2-D scrolling asteroid belt. The object is simply to survive for as long as possible. You have three lives.
The game is written partially in BASIC, but rather than taking the easy option of using the built-in ROM scroll routine, this game instead opts for the rather more tricky to implement horizontal scrolling, which is achieved by some small custom machine code routines, loaded into RAM at the start of the game.
Your spacecraft flies through the asteroid field, effectively travelling towards the left. I know this is completely irrational of me but it just seems that this is the wrong direction. I think it should travel to the right! I just find this a bit disorientating, but maybe it's just me. After all, there are many games where you can travel in both directions. I've probably played too many where you can only travel towards the right.
On the positive side, the machine code routines make the game possible to run at a fast rate and the asteroid and ship "sprites" are very well done given the limitations of working with UDGs. The game is genuinely challenging and a fair test of player reaction times.
On the negative side, you cannot achieve a score higher than 1279 as once the score reaches 1280 it generates error "B Integer out of range". I suspect the game was meant to be open-ended with no reasonable limits on the score. However I would say once you get the above error message you may consider yourself to have completed "mission". It's no easy task to get that far in the game.
Also, you can erase the asteroids by moving your ship sideways into them, when I would have thought that doing this should really cause you to lose a life. The ship sprite flickers quite badly, but I guess it can't be helped due to the continuous scrolling.
The game's OK for a quick session of a few minutes or so, but there are dozens of similar titles on the speccy and this one is essentially a minimalist version in a crowded sub-genre. Other versions tend to sport things like limited-use defence shields and so on. But certainly, mission would have benefitted from slightly more rigourous playtesting.
