All right, so Xevious is this mysterious game where you are the pilot of the awesome ship Xevious. This ship can zap the enemies above and incinerate those below; but this game is far from a walk in the park. So let's break this down, shall we.

The first and most important thing to go over is the enemies and targets, there are many of them in this game, and it will be vital for you to know what to expect from each enemy, as well as the reward for taking them down. Unfortunately, there is no score table in the game, so I had to gather this information through observation. I have tested them all several times to ensure accuracy, but there still could be a human error. So please bear with me. Most of these enemies are unnamed, so I will name them based on their descriptions. I haven't gotten too far in this game...only to area four, so I will edit in more info later on as needed.

Flying Saucer: 30 points
At first these guys do not fire a shot at you, but as you get into it they will shoot you from behind if you are not careful. There is no point difference in points value between the shooting and non-shooting ones, contrary to my original measurements. Their motion pattern tends to be to fly straight towards the bottom of the screen, but they will veer off to the sides if you get close.

Flying Fighters: 150 points
This I checked several times! These flying fighters will zip right in and take aim quickly. They are pretty good at tracking you, so you have to be careful with these guys. As far as I can tell, these guys are the fastest in the air. They like to fly right at you and then scoot forward diagonally and go of the side of the screen.

Flying Tank: 50 points
They look similar to a tank, but they fly! They are more aggressive than the saucers but less direct than the fighters. Their speed is also less than the fighters. They go towards your direction and fire, and then move off to the side of the screen going sharply backwards.

Wierd Saucer:???
This thing almost seems tank-like, but is shaped like a saucer. Its movement is more horizontal.

Invincible Plates: .....
There is no defeating these things! To me, these are the bane of this game! Typically, they just tumble your way, blocking your air shots, while the enemies can shoot directly at you! Fortunately, your bombs can go past these abominations.

Super Saucer: ???
Towards the end of area four (as it is designated in the arrangement) There lies an extremely mean boss. You have to hit his center in order to beat him, but that is easier said than done. The whole time, he is shooting air bombs at you and indestructible shots. This beast will relentlessly barrage you until someone wins. I did not beat this freak and take a look at the score yet, so I cannot say on that. My advice with this guy? Keep moving. Do not let him corner you!

Air Bombs: ???
I have so far been unable to measure the points on these, but they are little bombs that you can shoot, but they can also shoot you! They are extremely deadly in tandem with the Super Saucer's barrage of shots. Motion Pattern: Straight Forward.

Sparks: ???
That's what I call them anyway. They just look like a spark to me. I have not been able to measure the points on these guys either, on account of the speed of the game, and the fact that I cannot pause this one. They try to hone in to you, but are not extremely accurate. 

Ground Cannon: 300 points
Ground enemy that simply fires at you. A well aimed bomb is all that's needed for this wuss.

Super Ground Cannon: 1000 points
It is bigger than the regular one, and has a little black and red in it. Other than that, I am not sure there is any difference.

Five Cannon Combo: 2000 points (If you strike the middle first)
I really do not know the points given if you hit on of the others first. This set of five guns is loaded and ready to cut you down. Be careful around this dangerous ground enemy.

Normal Tank: 400 points
Black rectangular tank that really does not seem to do much. Slow movement makes it an easy target.

Spherical Tank: 800 points
Faster moving tank that drives along a set path and tries to shoot you.

Super Spherical Tank: 1300 points.
This dark beast moves and shoots much faster than any of the other tanks. Approach with caution.

Square storage building: 100 points
Nothing much here...

Circular Storage building: 200 points
Has more room for storage...

Super Square Storage: 500 points
A large target that is often defended by other enemies.

Super Item Storage: 1000 points
Destroying this will release an upgrade for your zapper. Only one upgrade allowed. If you already have one and you get another you earn 2000 points. If you collect three without being shot down, you get 4000 points for the third one. I do not know past that yet. I shall have to get better before I can say!

Now that we went over the enemies, I should go over a couple things that have crossed my mind while playing this game.

1. What is the best position to be in and why? 
In all honesty, it depends. If you are after the saucers, or even the flying tanks, towards the top of the screen is a good spot to take them down quickly. I would advise retreating for the fighters, because they come in diagonally, and are very fast shooters. You'll get hit if you are at the top of the screen.

2. I have been able to take down two buildings at once. Do I get extra points for that?
The answer is no. I used to think that you did, but after careful calculations and observations, I know that you will only get the sum of the two targets that you took out.

This is a mysterious and fast-pace arcade game. Keep moving, keep shooting, and stay alive!