I didn't quite get to the end of Final Fantasy XIII-2. It's a shame, truly, because my journey through the game was almost definitely the most fun I've had with a JRPG in a long time. However, there's a new contender for 'most frustrating last boss ever', at least in my eyes. Spoilers, obviously.
The final boss comes a bit out of nowhere. It's three Bahamuts, two of which are less powerful and a third one with more than a million HP. You need to beat the first two before being able to fight the third, and they regenerate fairly often. I was using a strategy I found on the internet which was working pretty well for me.
You have to stay on your toes during the battle to quickly swap Paradigms so you take less damage. It's a stressful experience because you can't take your eyes of the screen for even a second, because if you miss them advertising an attack and you don't switch to Sentinel quick enough, it's game over. It was on my third attempt when I quit.
I'm not someone who can sit down and do the same bit over and over. The third time, I was 30 minutes into the battle and the main Bahamut was almost down to half HP. I was keeping my HP up religiously and one of the lesser Bahamuts regenerated back into battle. He used an attack I'd survived many times already but I went to swap to Sentinel anyway. I wasn't quick enough, and that attack that shouldn't have killed 3 fully-healed characters, did.
I haven't lost so much good will to a game so quickly in a long time. I loved the journey, truly I did. I like the battles, I love the stat-balancing, I love finding fragments and I even thought the story was pretty good. But I just can't deal with final bosses that take an age to beat and have attacks that kill you in one hit. I really, really can't. Give him loads of HP, fine. Give him super strong attacks, fine. But don't, for the love of god, give him both.
Up until now, this game was a certain 5 stars. But after that battle, I just can't bring myself to because I'm too bitter. 4/5 stars.