I'm making headway on the Boss level and its mechanics, and have come to a crossroad. The most memorable bosses in games have a pattern they follow with slight deviation depending on what the player is doing around them.
This is because the player likes to learn and get a feel of what the enemy is going to do next. So through trial and error, they eventually defeat the Boss through repetition.
Another way is still with a set list of motions, but in a more random order (and better AI?). This is usually more challenging, but I'm not sure if it is more rewarding.
The animations usually offer some anticipation to give you a quick hint of what's going to happen next, which keeps you on your toes!
The battle goes through stages, so there will be three separate patterned attack sequences. And because of these stages, I can only imagine a random like mechanic to become frustrating as the variations multiply.
So, I'm leaning towards the pattern like mechanic. I don't intend the player to keep dying until they get it right however. As I don't want it to be too difficult for this first episode, it just needs to be fun!