It's not like there's a plot, you know. Just shoot the invaders as they come!
There are 4294967296 levels, since Flash doesn't know more numbers. Everything is procedurally generated, from enemy graphics (rather uncountable number of those) through their formations (at least several thousands of unique formations) up to the powerups (there are 32 of these).
And it's all packed in 50 kilobytes (It would fit on a Commodore 64)
This game requires hardware accelerated Flash Player 11 graphics!
Q. The game runs soooo slow...
A. You lack hardware acceleration see next question
Q. I see "No hardware acceleration" warning
A. The game uses latest Stage3D feature (hardware accelerated 3D graphics in flash). But as it's moderately new, there are still issues. Here are some things you can do:
1. Update drivers (seriously) drivers get fixes for flash player all the time, keep up!
2. Refresh cache ( hit Ctrl-F5 few times), there is a special HTML parameter needed, and you may not receive it, since old version of embed code is being cached on your hard drive.
3. Check if your hardware is supported: http://kb2.adobe.com/cps/
(note this line: " [unsupported] Any Intel GMA driver before X.X.10.2021" )
4. Right click the game, choose settings, and tick the 'Enable hw acceleration' box. If this game lags too much, do this on other flash game and refresh this tab.
5. Google up to get compatible! There are more Stage3D games coming!
Q. The game doesn't run at all
A. You need to update Flash Player to version 11 (even if you don't want to play this), furtherly see point 2. above.
Q. Why do you make space invaders that have higher requirements than Skyrim?
A. Fun! I love making games! I did this overnight actually for Mini LD competition http://www.ludumdare.com/
I didn't see the incompatibility issues coming. I guess it's a good incentive for everyone to get FP11 3D stuff up and running. There is a ton of Stage3D awesomeness out there, and more is coming!