Games where the final boss is actually the most difficult required boss

I don't even have an example because I can't remember the last time I came across it in a game. I'm sure I must have at some point, but it always seems like when I finish the final boss, I'm always remembering how some earlier boss was harder. It's always a bummer!

So, any examples of when this is not the case? And, as stated in the title, this is excluding optional bosses that are designed to be overpowered.
I've seen so many games reduce the final boss to a QTE or a simplified battle using the Game's Special Weapon that I now believe it's an intentional design decision everyone has adopted. Like they figure by the end the player is ready for the story to be over and they don't want the pace of the storytelling to be ruined by having to repeat a boss battle 36 times.

But you know, lots of movies do this, too. The longest and most complex fight is never the main guy - it's always against the badass henchman. Then the main bad guy dies just by getting shot out of a window or something and falling in slow-mo to his death. Maybe games are just imitating that.
Not a great game but it sticks in my mind because the final boss made me give up on it a few years back - last gen's Conan. Final boss was significantly harder than anything before.
Bloodborne. Works for both the main game and the DLC I think.
I have to disagree at least with the base game. Gehrman and Moon Presence were way too easy. Gehrman was tougher but got it done my second shot. I had only 6 vials left and easily killed Moon Presence. For a final boss it was a joke. The DLC bosses were difficult though. I had to summon help for Kos + Laurence. Every other boss I did solo.
Mario & Luigi: Superstar Saga
Never beat the game as the boss was terribly overpowered and took away all health after the first part of the boss fight.
Dark Cloud! Actually I'm not sure if it is even the last boss because I rage quit and never came back. I enjoyed the rest of the game, but the difficulty spike at that boss was absurd. Wasn't about to go grinding for the first time after putting in 30 hours.
I don't dislike diffecult bosses.
Only if:

- it's about the gameplay of your character and not because of bad gameplay.
- The boss ai is smart and not about a boss just trowing 100 rockets to make it diffecult.

Thats why most games are way overrated about the diffeculty, it's more about luck instead of skills.
The Last Remnant. It has optional super bosses but they're at the very best, as hard as the final boss but that's probably pushing it. Hardest super boss has a 10 round timer that makes the challenge. The last boss is just a savage onslaught
I struggled a lot against Dark Souls' for some reason, but I've heard he can be parried to death and for some reason I didn't even attempt it.

Metal Gear Rising ane Furi were pretty insane too haha.

Bloodborne. Works for both the main game and the DLC I think.
A lot of bosses in Bloodborne were quite challenging, but the final boss (es) are pretty much the only ones I beat first try lol, I found them disappointingly easy given how cool the fights look.
I was gonna say this. No one in the game touches Armstrong in difficulty, and he's even harder on Jet stream Sam's story.
Beautiful thing about Armstrong is that he's a test of all the skills you need to have mastered to beat every boss. He really feels like he's the endgame because of that.
Dark Souls 1. I was almost in tears of frustration trying to defeat Gwyn. He moves way too fast and I suck at parrying. It took me 19 tries. Don't think I'd struggle as much now that I've played Bloodborne where bosses require quicker thinking and reactions. Going back to Dark Souls and all the bosses feel so sluggish and give you plenty of time to react.