Yeah, I'm not entirely happy with how the boss fight goes (considering there's a bug where the boss won't jump properly which is why it stands in place)
I have it shoot at random intervals but I found in testing that if the intervals are too short you get very few chances to hit the boss, and you're more likely to die too quickly without some sort of indication of when the boss will fire.
I will be working on fixing that in an update with some other bug fixes like the lack of jumping from the boss.
Thanks for the feedback!