Here's a WIP of the first stage. It lacks the background and sprites. I've also discovered that the water has a cycling palette, but I think it will be relatively easy to fix.
Also, I'm not sure about how to number the stages, because according to Wikipedia:
The original arcade version features ten stages according to the promotional flyer, counting the two "homicide sensor" bosses after the base stages as separate stages. The final four stages in the game (the snowfield, the energy zone, the hangar and the alien lair) all take place in one continuous level.
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Dot? Dot. Dot!