Zeroptian Invasion Walkthrough

3. Story walkthrough

Again, the game is very simple. Move left and right to avoid enemies and enemy fire, and fire to kill all the enemies. The first world consists of 3 levels, the second one of 4. You get a checkpoint after level 3. You can continue as many times as you want. You only get 2 lives, making the shield power-up a very powerful way to extend your life.

Aside from dying, the other achievements are all story-related or score-based. Between killing 3 levels' worth of enemies, the boss on the last stage, and the accuracy bonus you get, you're pretty much guaranteed to get all the score-based achievements for just clearing a world. Therefore, an argument could be made that all the score-based achievements are also story-based because you cannot not get them while clearing a world.

So your approach should be just to focus on clearing the first two worlds. Do farm power-ups to make your life easier as described in the hints and tips section.

Level 1 (L1)

This is a standard Galaga-like setup. You'll have a bunch of enemies and some shields that will slowly take damage and disappear. Simply whittle the enemies down to a few, and then farm power-ups before clearing the level to set yourself up. You can shoot down most projectiles in the game, but it's generally safer and easier to just avoid them.

There will be three rows of enemies. The enemies in the first 2 rows can only fire straight down and are worth 100 points each. The enemies at the very top row are worth 200 points each and will fire a diagonal shot aimed at where you are currently standing. You'll have to move out of your current location to dodge it.

You get 3 obstacles that act as shields. These will take damage over time and eventually disappear so you do want to take out enemies relatively quickly.

You should farm power-ups here. I'd recommend killing the top row of enemies since they fire the shots most likely to kill you and leaving some of the lower row enemies alive.

If you die you'll get:

Welcome in Zeroptian Invasion
Welcome80 (80)
Die for the first time
  • Unlocked by 3,125 tracked gamers (100% - TA Ratio = 1.00) 3,131

Simply killing all the enemies on the level guarantees the first score based achievement:

Don't give up in Zeroptian Invasion
Get 1000 score
  • Unlocked by 3,116 tracked gamers (100% - TA Ratio = 1.00) 3,131

When you grab your first power-up you'll unlock the following achievement:

Boosted in Zeroptian Invasion
Boosted80 (80)
Get a power up
  • Unlocked by 3,102 tracked gamers (99% - TA Ratio = 1.00) 3,131

Level 2 (L2)

Another standard Galaga-like setup. Same strategy as the first level.

You'll only get 2 obstacles that act as shields. There will also be 4 rows of enemies. The first 3 can only fire straight down. The topmost row has the diagonal shooting ones.

Simply killing all the enemies on the first two levels guarantees the second score-based achievement:

Good job in Zeroptian Invasion
Good job80 (80)
Get 2000 score
  • Unlocked by 3,103 tracked gamers (99% - TA Ratio = 1.00) 3,131

Level 3 (L3)

A final level of vanilla Galaga-like setup. There's a boss at the end once you kill all the enemies.

Again you will have 4 rows of enemies with the first 3 rows shooting straight down and the top-most row firing diagonally. There will be just slightly more of them than in the last level. You only get one obstacle this time around, but it can't be destroyed... because it'll transform into the boss once all the enemies are dead.

The first boss is pretty straightforward. It will fly around in a vertical figure-8 and fire several projectiles at a time at you. There's an eye in the middle which you need to aim for in order to damage it. It'll take about 10 hits.

You're are also guaranteed to hit 5000 points during this level getting you the 3rd score-based achievement (as a reference, with a couple of duplicate power-ups I was at 6950):

Well done in Zeroptian Invasion
Well done81 (80)
Get 5000 score
  • Unlocked by 3,031 tracked gamers (97% - TA Ratio = 1.01) 3,131

For beating the boss and completing level 3 you will get the following achievements:

A hidden enemy in Zeroptian Invasion
Destroy the boss of the first area
  • Unlocked by 2,912 tracked gamers (93% - TA Ratio = 1.03) 3,131

Going forward in Zeroptian Invasion
Complete 3 levels
  • Unlocked by 2,910 tracked gamers (93% - TA Ratio = 1.03) 3,131

You'll get an accuracy score bonus at the end of the level as well. It's your accuracy * 100. So long as you get somewhere around 50%, you'll get 5000 points, or half the points for the last score related achievement. Combined with the guaranteed 5000 from the enemies from the first 3 levels, this should push you far enough to 10000 and the last score based achievement:

That will teach them in Zeroptian Invasion
Get 10000 score
  • Unlocked by 2,863 tracked gamers (91% - TA Ratio = 1.04) 3,131

Level 4 (R2)

You get a checkpoint here. If you lose all your lives, when you continue you will now start here.

This is a transitional/travel level setup. It's similar to the bonus levels from Galaga. Enemies will fly down in a group of 5 in set patterns. There will be 4 waves. You can kill them but don't have to. They do fire diagonal bullets aimed at your current location. They will eventually fly through the bottom of the screen and you'll complete the level regardless. You cannot farm power-ups on this level.

Level 5 (L4)

We're back to the standard Galaga setup again. And that will be the setup for the next 3 levels.

You get 2 moving platforms that serve as shields that will eventually be whittled down.

There are 4 rows of enemies. There are spiders that will shoot spiderwebs that don't actually hurt you (but do slow you down). You can't shoot spiderwebs down. The last row of enemies also now takes 2 hits to kill. However, all of the enemies can only fire straight down. In some ways this setup is actually easier than the enemies that fire at you. Depending on how you kill the top row of enemies (generally if you do it before clearing the column) the enemies will give you a bonus 500 points (not that you should need points anymore).

There will also be a random boomerang-looking projectile that zigzags in a column. It can be shot down for 200 points, but it's probably just easier to stay out of that column.

After completing this level you'll get the following achievement:

Excellent in Zeroptian Invasion
Excellent84 (80)
Complete 5 levels
  • Unlocked by 2,829 tracked gamers (90% - TA Ratio = 1.05) 3,131

Level 6 (L5)

You only get one moving platform to serve as a shield.

Again there are 4 rows of enemies. Same setup as the level before, just slightly more enemies.

Additionally, there's a column in the middle that will have falling rocks. You need to avoid these and they will block your bullets.

Level 7 (L6)

The final level you need to beat, and it has a giant spider web as its background. (A spider web in space... don't ask).

There is no obstacle for you to use as a shield, but the enemies start very far up and there are no hazards.

There are again 4 rows of enemies, but this time the enemies that take two hits are in the middle of the 3rd row. The enemies are also mostly spiders making it easy to use this level to farm powers ups. You should farm power-ups because there's a boss at the end.

Once all the enemies are dead, the boss will crawl up from the bottom of the screen. There will be three !!! indicating where he will spawn so you do not want to stand there. The boss looks like a bee/caterpillar hybrid (because bees/caterpillars weave webs) and it's a lot larger than the first boss. However, like the first boss it shoots a bunch of projectiles. Like the first boss the weak point is in the center, in this case the stinger. This boss will also spawn red orbs that will bounce around the entire screen. These can be shot down with 2 shots. I found it easier to just ignore them and take the boss out quickly. You'll have to hit the boss about 15 times to kill it. Once you do you'll unlock the last 2 achievements in the game.

A messy enemy in Zeroptian Invasion
Destroy the boss of the second area
  • Unlocked by 2,293 tracked gamers (73% - TA Ratio = 1.16) 3,131

Impressive in Zeroptian Invasion
Impressive234 (200)
Complete 7 levels
  • Unlocked by 2,292 tracked gamers (73% - TA Ratio = 1.16) 3,131

Congratulations on the 1000GS and another completion!

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