One of my favourite series. Started with vanilla P3 back when it was released, during the golden era of PS2 JRPGs, then put hundreds of hours into P4, P3P, P4 Golden and P5, both royal and original. Also went back to check out the first Persona and two P2 games.

P2 and P2 aren't really "Persona" games, they are "Shin Megami Tensei: Persona" games. Dungeon crawlers with random battles. Unlike more modern Persona games, you don't go to school in these games, you go out of it by beating the shit out of demons. No school life simulator, no social links, just good ol' 10% story + 90% battles. I love P2's story, though. It's the most... entertaining, I'd say, and definitely feels different compared to other Persona games. Probably because the characters are mainly adults. If you decide to give it a try, beware that it has two games and the second is the direct continuation of the first. Hope it gets remade as well someday. It's also the best Persona game in terms of demon negotiation. The player can choose one or several members of the party and make them do a comedy act, play violin, tell jokes etc. to acquire persona cards. It's a lot of fun to explore these little scenes, as they change with the story's progression. P5 sort of added demon negotiation back, but in its early SMT form of "answer the question right". It's not even half as fun.

New Persona games are more or less similar, the main difference is the theme and the mood. P3 is blue and depressive, P4 is yellow and fun (but also a bit unhealthy), P5 is red and adventurous. P3 was a true revolution, as it added school life simulator aspects to an existing SMT formula. P4 and P5 use the same formula that was invented for P3, and it's my main issue with Persona series. It doesn't progress anymore. P4 being the same as P3 was understandable, as these games are a couple of years apart and were released for the same system. P5 being the same as the two previous games isn't exciting at all. Yeah, it has better UI, QoL features, of course, better graphics, animations and everything else one might expect from a newer game. However P5's core is the same as P3 and P4, and this core is immersion. At which P5, imo, is worse than P3 and P4. Can't really pinpoint why, maybe its aesthetics are the reason, or the less believable, too grandiose setting. It went from "we are saving the world behind the curtains, but nobody knows it" (P3) and "we are solving a crime case and saving the world, but nobody knows it" (P4) to "we are defeating all sorts of evil people and saving the world and everyone sort of knows it" (P5). P5 felt less immersive than previous games to me. Compare Joker to P3's MC - a chad Arsène Lupin who happens to go to school sometimes vs. a sad emo boy always with headphones on. I liked more down to earth and realistic approach of P3 and P4 in that regard. School life in P5 felt as an honestly unneeded afterthought. Another thing that broke immersion in P5 specifically for me is social links, pardon, confidants mechanic that was too centered on gameplay. In P3 and P4 you could do a run without some social links just because you felt like it, but in P5 your freedom of choice is severely affected by passive abilities gained by meeting with certain confidants. I dislike the game dictating me which confidants I have to prioritise. Don't get me wrong, P5 is a very good game on its own, it's just some things about it rub me the wrong way when I compare it to other games.

btw, I always thought that P3 OST is so unusual because it was composed with the idea that it's the music that the MC listens to first and a game soundtrack second

P3 is one of my favourite games ever. Story, music, characters, art, gameplay - everything is stellar. Haven't yet tried the Reload version, because Atlus taught me to never buy their games before the definitive edition is released. I'll probably wait until the female MC is available. Anyway, I like it more than other Persona games due to how deep and immersive it is. It's the only modern Persona where relationships within the party felt natural to me, where party members didn't instantly become bff just because they shared the same goal. I liked the tension between Mitsuru and Yukari, Junpei's ambitions, Ken's animosity and so on. I enjoyed that the characters were wary of the MC at first and slowly opened up to them. P4 and P5 are a bit more "nakama power" in that regard. Notice how party dynamics remain unchangeable in P4 and P5 - once you get a new character, their story is more or less done and they behave the exact same way until the end of the game. And it's always "one dungeon - one new party character" policy. P3 has less predictable structure.

Didn't say much about P4, but it's also an excellent game, with the best humour in the series.