I got this game years ago back when I had a shitty laptop and got frustrated with it in the first area because playing a controller or wasd+mouse game with a trackpad is not a good idea LOL, but later I came back to it with a controller and ended up getting completely sucked in and playing through the whole game in like 2 days. I've since done 3 more playthroughs and each one felt relatively fresh even though the game has some non-replayable elements like puzzle solving. My most recent 100% playthough was incredibly rewarding and I'm sad I can't really do much more with the game unless I get into speedrunning or challenge runs.
As a singleplayer action game, I think it's easily one of the best of all time.
The game is mostly split into the level design in the overworld and dungeons, the combat and the atmosphere/story and while I've seen reviews where people liked some aspects and not others, all 3 of them absolutely excel to me.
For the overworld level design, The first couple areas have fun platforming challenges and stay interesting, but the game really takes off in Maroon Valley. Every subsequent area feels like a more and more complex puzzle that you are slowly chipping away at until it eventually untangles. The game's main tool for designing areas is playing with verticality. When you enter an area you'll go through the lower main path and see tons of treasures and paths that are on higher ground or blocked off and eventually you'll find some way to climb up, and then you start chipping away at the puzzle by finding where you can get to, what switches you can hit to open up new paths to higher ground in different locations and so on and so forth. Once you've fully explored an area it's easy to get around when you're later asked to do so for quests, to find the last couple chests, or to travel through the whole area on a massive combo.
The dungeons are where most of the criticism online I've seen goes, saying that there are too many puzzles. But honestly when I played I'd almost say there were too many combat encounters and I was hungry for more puzzles lol. Even on a replay, I found most of them pretty fun to pull off, and the easy or tedious ones early on can often be skipped with movement tech that the game doesn't directly teach you, but does show is possible in a late-game quest. I didn't really get stuck with any of the puzzles at any point in the game except for one in the fire temple that I found obvious on the second playthough, but in my first run I ended up brute-force cheesing it (Involved getting two frozen bubbles to clear a path over lava, but I got a precise set-up to do it in one). Maybe these would be a lot more frustrating if you repeatedly got stuck on them but like idk skill issue I guess? The game has accessibility settings for puzzle speed, so once you find the solution, execution shouldn't be a hurdle unless you want it to be.
On the subject of accessibility, while accessibility settings are nice, I think they might actually be a detriment to the combat side of things since they're too easy to access when the game should be making you rethink your strategy. The combat in crosscode is super engaging and has massive variety based on choices in equipment and in the multiple skill trees. I do think it's a shame you spend quite a while with only 2 elements or fewer and having all 4 is something you only get to enjoy later in the game, but the DLC fixes this pacing issue and makes the game feel pretty balanced in terms of progression. It's dynamic with enemies having very varied patterns and especially in the PVP bosses you really feel tested on quickly reacting to the situation at hand (unless you cheese the early ones with Guard Sphere).
I found the difficulty pretty high on my first playthough, but on that run I basially never used the guard function and my equipment was underlevelled in the midgame. Later playthroughs where I stayed on-top of the equipment levels and actually used Guard Arts were very easy, although knowing enemy patterns certainly contributed. That said, I didn't finish the DLC on my first playthough because I wanted to play the main game again more thoroughly before buying, so the DLC was fresh to me and despite hearing that the (kinda) final boss was very hard, with a defensive build and equipment that was on-level I was able to beat it with very little difficulty. (Royal Guard and Riposte gear are OP, rush the shield buffs in the Cold skill tree to trivialise the game).
That's why I feel the game's super easy to access difficulty sliders could be a detriment to some players, letting them force through without engaging in the game's systems. It's very open to more agressive or defensive playstyles, with tons of different combat arts and melee and ranged options. Consumables are also really powerful in the game but not necessary, so using them is another way to configure your experience.
You are really able to pick your own difficulty through the game's mechanics with how many quests you choose to do and when you choose to grind for equipment. If you take the time and grind out new equips at the start of each area, the game is easy. Taking only what you can get through quest rewards and drops from enemies without grinding, the challenge is pretty fair but not insurmountable. You can get away with basically speedrunning the game and ignoring all non-mandatory combat, but it'll be damn hard when you get to bosses or forced encounters. Level isn't nearly as important than Equipment and you can't get too underlevelled with scaling xp, so sidequests are the main way to get more powerful since the equipment you can outright buy instead of trading for is crappy.
The story and atmosphere are very good. The plot had some parts that were touching but it's nothing revolutionary. In the end though, I don't really go to games for the story so this wasn't a huge factor for me. The game is consistently really pretty especially in Sapphire Ridge and the music is always solid, although I'll admit none besides Shizuka's theme really amazed me. The game is able to sell the false MMO premise decently well although it's not gonna immerse you into thinking it's actually multiplayer. Animations and sound effects are very fluid.
Overall the game was basically the perfect singleplayer linear experience for me. It feels like a perfection of the formula started by the 2D zelda games but with some RPG elements that make it a lot more customizable of an experience.
