Topic: What do you look for in a boss battle?

Great boss battles often have very memorable music, maintain a decent level of challenge, and often subvert expectations and/or creatively play around with game mechanics. Extra points if there is some level of emotional intensity or narrative tension to the fight. Examples of great bosses that come to mind are DJ Octavio from Splatoon, Psycho Mantis from the original Metal Gear Solid, Jenova Life from FF7, (Bravely Default and Undertale spoilers) Omega Flowey and Sans from Undertale, and Airy's final form and Ouroboros from Bravely Default.

Ignoring the obvious presentation aspects of a final boss (music and visuals), I like small-scale fights emphasizing mechanical mastery. Sure, fighting giant things is pretty awesome, but besting a skilled opponent that can easily mow you down if you're not paying attention is, in my opinion, far more satisfying.

I tend to really like boss battles that follow the Zelda boss formula in interesting ways.

But I also really love bosses where you can take a lot of hits, yet the boss can still take so much more. I'm pretty sure half of my favorite bosses are from 3 games (the 2 No More Heroes games and Little King's Story) partially for that reason.

I just like the boss battles that run smoothly w/o forcing weird instances or repetition on the player. Pokemon is kind of repetitive, but the GCN games made the bosses more special than in the main series, IMO. Alot of it has to do with the presentation, because some boss battles are amusing, even if they are easy.

I think Boss Battles just need to provide something different. Something that makes them stand out. When Boss Battles are too similar to normal battles it gets boring. That doesn't mean different gameplay or anything, sometimes it can just mean a different look. For Pokemon games the exciting part of fighting Gym Leaders or Elite 4 is seeing new powerful pokemon. In Platforming games it is normally a bigger than average enemy that takes multiple hits to defeat. If the Boss Battle is too similar to normal battles then you most likely won't remember it. Different things stand out for different people and that makes it difficult to create memorable boss battles but some designers have done a good job at that.

I agree that the Zelda boss formula is pretty good, but the actual quality of 3D Zelda bosses is surprisingly weak in my opinion. My main gripe is that a good number of Zelda bosses are either non-threatening or involve copious amounts of waiting. Say what you will about the design of the Imprisoned, but at least it feels like you can't just stand around doing nothing and not lose the game as you do with bosses like Argorok and Morpheel.

I know I said I liked the exact opposite of this in my post, but I totally agree with you as well.

Significantly sized reward for beating them. I don't care if the boss was weak, OPed, unique, or a ripoff. As long as it was worth it, I'm good.