I am so glad I decided to play this game - I initially thought the graphics looked a little bit cheap in the screenshots and trailers, and I can't believe how wrong I was. They are absolutely beautiful, I was constantly just stopping, staring at the backgrounds in awe, and the character and enemy sprites are just delightful.
When it comes to gameplay, this is the exact type of gameplay I like in a game. It is super simple. You run, you jump, you have a basic sword swing, and that's it. No fancy combos or special abilities for me, please! Enemies follow basic patterns as well.
There are special abilities in this game though, and that's unfortunately an area that isn't super well designed imo. There are 5 subweapons/magic spells, essentially, but they drop as items, so you need to, like, kill enough enemies to have a fireball drop, then when you use it once, it is gone. You don't really get a ton of these, which means you're very limited, and the kicker is that the spells aren't even very strong. I'd expect a spell to at least take out an enemy in one hit, but they take two or three sometimes. And most of them just aren't particularly useful either way, except using the upward-attacking-arrow spell to hit things above you, and the tornado which hits things below you. These are useful against a small variety of enemies, depending on the terrain.
But the other issue is you lose all of your items when you die. Dying otherwise has no penalty, you just return to town and keep your money. That's fine, but you lose all the spells you've accumulated, so you kind of are always in two states: a) you have more spells than you know what to do with, because you're barely using them, or b) you have 0 at the time you actually do need one. It's just strange design decisions all around here. It sort of reminded me of Chasm, another game where the subweapons were not designed very well.
Anyway, level design is simple but nice. A lot of areas just sort of running forward through horizontal screens, sometimes mazes, often a gimmick where you need to take the correct path off the screen without knowing which path is correct, and then a few areas where the horizontal path also has an underwater area under it, which is really the only time areas feel expansive.
The game is sort of Metroidvania-ish, sort of not. You do get abilities, and I found it so interesting how you get locked in to them - each of your monster forms has its own unique advantage for getting around the map, but once you change monster form via plot progression, you can't keep changing! (Until later when you start to find rooms or items that let you change) It's sort of like if you were playing a Metroid game and you got the morph ball, but then you got the double jump and could no longer morph ball, and then you get ice missiles but can no longer morph or double jump. It's a new dynamic, and even though it's sort of restrictive and not necessary, it was cool. Unfortunately, once you do need to start switching, it's very annoying to have to do so in specific rooms, and it takes a long time even within that room.
Boss fights are an issue. They are very strangely designed. The bosses are so simple, they follow basically the same pattern the whole fight and there's really nothing interesting happening in them. You can get hit a bunch and still win by just smacking them.
Equipment is weird as well. Stats scale really weirdly. Going into a new area, I found a shop selling a weapon that doubled my attack. I didn't have enough money for it, so I thought, that's fine, I'll kill things slower, no problem. I reach the end of the area, no problem, but then I face the boss. It has 100 HP, and each of my hits does 1 damage, and I can only hit the boss once per cycle. Against other bosses, I can do 10 damage! I died because it was unbeatable, I bought the weapon, I got to the boss again, did 14 damage per hit and won without trying. I understand that a new weapon should be a new deal, but it being the difference between unwinnable and cakewalk was really awkward.
Besides that, there's a sort of gimmick where each form gets different stat bonuses from different equipment, but it's sort of just an illusion of depth - In reality, it just means spending more time opening the menu and switching to whatever has the highest number. You also sometimes have to switch equipment to use certain abilities, which you switch to, use for a moment, and then switch back. Again, clever idea, but just a time waster.
The soundtrack is phenomenal, there are some really amazing themes that will for sure rank among my favourites for a long time, and the level themes are all super catchy.
There are some bonus levels which are designed to have more difficult platforming and enemy challenges, and they are sadly just awkward and sometimes frustrating. The game works best when it sticks to its simple level design, which isn't mindblowing, but is fun. It tries to do more unique things in these hidden bonus levels, and it sort of shows the weaknesses of the level design. (I think they are copied over exactly from the original non-remake, so this makes sense?) The bonus levels try to use enemies and obstacles in clever ways that make you have to think about how to proceed, but nothing deals enough damage to matter, so you can just blow through them. Either that or some of the areas have parts where getting hit once means you fall down and have to restart the whole area, which crosses to the other end of the spectrum and becomes super frustrating!
Anyway, it sounds like all I have are complaints, but that's because there's more words needed to describe what the game does wrong, and these are interesting flaws I wanted to note. But ultimately, the graphics, soundtrack, and simple gameplay are just super charming and fun and I very much enjoyed it.