I've hit upon a new technique for coding custom bosses, which I'm amazed I didn't think of before. I call it "ghosting." Essentially it's just telling the game to create an invisible enemy, like shooters, or the fire enemy, and then having that enemy move along with an FFC. Secondly, linking each active FFC in your large boss to a single "mover" FFC means that you can control the boss' movement realitively easily.

I cannot stress enough how much FASTER this way of making bosses is. I've made five or so custom bosses in the last two days illustrating these techniques and added them to this quest. The script file is included in the zip.
http://users.sephiroth.ws/C-Dawg/SideQuest.zip

Here are screenshots of some of the bosses in action.

This fella flies around after your ship, shooting fireballs at you. It turns to follow you, but it has inertia, so you can avoid it as it swoops by. 150 hit points.


This one drifts back and forth, spits out highly damaging bubbles that slowly drift downscreen, and it shoots fireballs. Has about 150 hit points.


This boss (not accessible yet) slowly follows the player while spitting out eyeballs (keese, bats) and fireballs. 200 hit points.


This son of a bitch zips around the screen in a wave motion while shooting at you. 100 hit points.


Now, if only FFCs would display the proper Cset and not just Cset 0, these bosses would look alot better...