- Estimated achievement difficulty: 1/10
- Offline: 12 
- Online: 0 
- Approximate amount of time to 200: 30 mins – 1 hour
- Minimum number of playthroughs needed: 1
- Number of missable achievements: 0
- Glitched achievements: None
- Do cheats disable achievements: No
Galaga is a great game that has been around for years, well since 1981 to be precise. The objective of Galaga is to score as many points as possible by destroying insect-like enemies that fly around the screen and attempt to shoot at you, as well as collide into your fighter spaceship.
Welcome to Galaga! This game has a total of 12 achievements and requires only one playthrough in order to get the full 200 possible. I gave this game a 1/10 difficulty rating simply because if you die (run out of lives), the game has a continue feature that allows you to select up to the last level you completed, thus eliminating the need to replay the entire game. You also have the option of starting with four lives instead of only having three.
Step 1: Preparation
I can't really say too much for preparation. I guess it would be wise to do some thumb stretches and get ready to strafe and mash the button a lot.
Step 2: Play the Game
As you play through the game, you will gain many of the achievements naturally by progressing through each level. In case you are curious which levels you will attain certain achievements, below I've included a list.
- Level 2: Enemy Fighter & Dual-fighter
- Level 5: Scorpion
- Level 8: Stingray
- Level 10: Stage 10
- Level 11: Dragonfly
- Level 12: Galboss
- Level 19: Mosquito
- Level 20: Stage 20
- Level 30: Stage 30
- Level 31: Blue Spaceship
Note: For each achievement, regardless if you complete the level or die during that level, you will still unlock the achievements for the enemies as well as the stage achievements.
"Perfect Bonus": This achievement seems to be the one that most tend to have some troubles with. There is an excellent video located below in the Achievement Guide that will show you exactly how you earn this achievement.
Step 3: Mop Up
Once you complete the game, congratulations as you should have earned all if not most all of the achievements! The most difficult achievement to get, as mentioned above, is “Perfect Bonus” and even it isn't that bad with a little practice.
That's it! If you've gotten to this point and followed my advice you should have the complete 200 for this game.
[XBA would like to thank Ingles for this Roadmap]