Space Phantoms - Arcade (Zilec 1979) 

I was pretty stunned by it too, I first encountered it in a small arcade and it was a cocktail version with the sound cranked up,the floor felt like it was vibrating and with the mass of bullets flying at me the game left quite an impression. It is a clone of a game called `Ozma Wars`,the only difference is that the space ships have been changed to a Halloweens horror type theme.

@@JAMMAJUP01 Interesting because now I am wondering if it was actually Ozma wars I saw back in the day as the graphics look even more familiar. To think it was an early SNK game originally and what they went on to produce!