And even more infamous because the speccy's original version is not even that good to begin with.
*Graphics : the Amstrad version use unmodified Graphical DatasGraphic Data.
The Sprites and tiles are stored in RAM in 1bit per pixel, sprites are also masked in 1 bit per pixel. the 1bpp datas are data is then turned into Mode1 2bit per pixel when they are to be displayed into the Video RAM area. Which is somewhat CPU intensive.
*Also some Raster interrupt are used in order to get more than 4 colours displayed on the screen.
*As the sprites are 1bpp + 1bpp mask , this means that if properly recoded in 2bpp they use the exact same amount of DATA in RAM, but could then be in 3 colours, the 4th colour being used as a mask, s as used in super wonderboy (this is not shown on mock up)
*Also it may be possible to apply some king kind of "attribute colour" on the tiles so the Background and Foreground tiles, while still being 1bpp/2 colours...you may be able to set the ink (other than black) into one of the 3 other inks (from the Mode1 palette) as shown on the Map Mockup.
*Then get rid of Rasters interrupts/palette change to gain some CPU or even free the few minimal RAM needed by such routine..
There, you have a better version than the speccy one.
==Lazy port ?==
It is to notice also worth noting that the Disk version actually use uses multiloads as it seems to reload data between each levels. So it would seem that the Amstrad version is just a lazy, hurried port.
Such a shame for what used to be one of the best Arcade Game of 1987.