- Estimated achievement difficulty: 5/10
- Offline: 12 
- Online: 0
- Approximate amount of time to 200: 3-5 hours
- Minimum number of playthroughs needed: 1
- Number of missable achievements: 0
- Glitched achievements: None
- Do cheat codes disable achievements: No Cheats, and you are allowed to adjust the settings for achievements.
- Does difficulty affect achievements: N/A
Keep your eyes on the sky and on the ground for these twelve achievements. If you are really good, you could get 200 in a half hour, but several runs will be needed realistically with Xevious’ moderate difficulty.
In Xevious, you have two attacks. Ground and air. The game has achievements centered around both types, as well as finding hidden flags and bases embedded within the landscape, acquiring a high scores, and defeating a mothership. Before anything else, go into Options and change your setting for extra lives so that you get one every 40,000 pts. A warning pops up saying you can’t post scores on the leaderboards but achievements are still fair game. Remember, this is a Namco game, you get all your achievements after your game is over, just be patient.
Step #1- Points Run
Naturally, if you are going for High Scores, you will likely gather many of the other achievements along the way. The key to 100,000 points is grabbing easy points and extra lives. For easy points, take advantage of ground enemies. Many of them do not even shoot, and even the ones that do can net huge points and are worth the risk. Dodge the air enemies if you can and concentrate attacks on the ground. Of course, shooting down air enemies is important, as they will charge or shoot at you. Extra lives will come with points, but “Special Flags” hidden in the landscape will give you Extra Lives to extend your play. To reveal the flags wou have to blindly bomb the ground to get them to appear. Look for the first flag as you fly OVER the river in the first stage. There aren’t many enemies so I suggest grabbing this one for sure. A picture of the flag is located HERE, but remember flags are not always in the exact same spot. Flags do appear in the same horizontal plane in each spot, so spam the ground along that horizontal plane with bombs to reveal the flag. Flags are also located in Area 3, Area 5, and Area 7. If you can grab them safely do it but make sure you don’t die hopelessly looking for it. This may take you several tries to get a hang of things.
Step #2- Ground Run
If still don’t have the achievements for defeating 30 and 100 ground enemies, start from the first stage, and concentrate on ground enemies. Grab the first Special Flag for sure to stay alive longer, and kill air enemies only to avoid being killed. These must be done in one run, they are not stackable between playthroughs.
Step #3- Air Run
Destroying 500 enemies by air will be tricky. The method described in the Achievement Guide by Sajaa works very well. Start from the beginning, and kill as many air enemies as you can, but get killed before you cross the river where the Special Flag is. Repeat this method until you are down to your last life and you should have about 250-300 air enemies defeated. Now, while on your last life, concentrate on the air enemies as you try to stay alive as long as possible. Grab Special Flags (like the one in Stage 1) to extend your playthrough. Although you are trying to destroy air enemies, do not completely ignore the ground enemies, as they will net you some good points for more lives. Again, the 500 kills are not stackable, you must achieve this with only one set of lives.
Step #4- Special Flags, Secret Sol Citadels
By now you should have found a Special Flag, but if not, start from the beginning, and get to the river and spam it with bombs to reveal the flag. HERE is a screen of where the flag is, but remember the horizontal location changes in each run.
Col Citadels are secret towers also hidden in the landscape. It takes one bomb to reveal them, and another to destroy them. Start a new game but begin from Stage 9. The towers are shown in THIS SCREENSHOT. Reveal as many as you can then immediately die afterwards. You will start from Stage 9 again and you can reveal them again. Reveal 5 before all your lives are up for three achievements. You only need to destroy one of them for a fourth achievement.
Step #5- Andor Genesis! The mothership!
You probably destroyed it in your other runs, but if not, start from Stage 4 and get to the giant ship and bomb the middle of it to destroy it.
Not as easy as some other Namco retro titles, but obtainable with a little understanding of the game. All in all, a satisfying 200.
[XBA would like to thank litepink for this Roadmap]