Hypnotic and Zen like minimalistic shooter. A classic.
The movement of the enemy demons is rhythmic perfection. The simple sounds rising in pitch slowly raise your adrenaline through each wave. The box artwork by Imagic was fantastic compared to what Atari was putting out.
I liked this game and had to buy it when it first came out. Not long after I got the chance to play the 8 bit computer version and loved it. It was a few years before I was able to afford the computer to play it on.
And the only quirky thing about the game is that you warp back in after getting shot at the exact same spot often right back into enemy fire.
The Bottom Line
Wave after wave of demon birds descending on you dropping bombs and lasers trying to blow you up. They are very elusive and hard to hit. Some warping in to take the place of ones you blow up until you destroy the last in each wave. At higher levels they split in two as they get hit and then dive bomb your shooter. Shoot the bottom demon last that way it won't split and ones above can't split either. Make it through a wave without getting hit and get an extra shooter. You will need them.