**THIS REVIEW CONTAINS NO SPOILERS**
Flawed. This game is flawed as hell. Aquaria does a lot of things excellently, but also flounders on principle gameplay mechanics. For these reasons, I find it very difficult to decide if I want to give this game a Thumbs Up or Thumbs Down.
Ultimately, I will say Yes to recommending this game, but before you buy this, you need to ask yourself a few things. Do you enjoy the Metroidvania subgenre? Would you get great enjoyment out of exploration and appreciating the varied and well-done aesthetics? Would this enjoyment mean you could tolerate very long travel times between places you need to be while doing simplistic, shallow combat? If this sounds appealing to you, then buy Aquaria. $10 is a bargain.
Alright, down to the specifics.
I'll start with what I liked about the game, which is primarily the aesthetics. Aquaria, bar none, blows every other game I've ever played in my 20+ years of playing games out of the water when it comes to underwater levels. The game boasts a huge variety of marine biology, both plant and animal life. Each major area of the game has its own unique feel and theme, with unique sealife to match. I don't think I can recall any enemies that looked like an iterative version of an earlier one, even if some enemy's behaviors are similar. This game simply wows when it comes to the underwater places you'll go.
The music, while not quite the best I've heard for an indie game, gets the job done nicely. Each track is pleasant to listen to and generally fits the theme of the area you're in, even if they can be a bit too upbeat at times. Boss battle music feels a bit too quiet, but it's not the worst I've heard.
Naija, voiced by Jenna Sharpe, impressed me with her consistently good voice work for the game. Although the majority of the lines involve the main character talking to herself, she puts forth enough emotion to stop from sounding bored, and gives enough conviction to the more stressful moments for Naija to sound believable. Considering how bad many video games' voice acting is, this voicework was a breath of fresh air.
Unfortunately, Aquaria frustrated me when it came down to its gameplay mechanics, or at least the "feel" of them. The game, being a Metroidvania, primarily involves exploring and fighting things. Neither of these felt great to me, and it's for a few specific reasons.
Exploring the game's areas, as well as figuring out where to go, became tedious for me quickly and didn't really stop until the end. Aquaria, like many games in its subgenre, doesn't tell you exactly where to go next. Naturally, that means both wandering and using process-of-eliminiation to find your next desination, and those are big draws to playing games like these. However, this game makes those very tedious to go through due to both the huge size of the zones as well as the twisty, maze-like caverns that connect them. The minimap zooms in too much to the map, so I had to keep reopening my main map in order to not get lost. Furthermore, many times I sighed in frustration as I realized I'd have to cross a huge, enemy-filled zone in order to check if one spot on my map would lead me to somewhere relevant.
Normally, this wouldn't be too big an issue, if the game provided fast travel. Well, Aquaria does, but it involves finding turtles who will take you to another turtle's position, and you have to find at least two of these spots before you can use it. The turtles are spread few and far between, and often off the beaten path of a zone. Therefore, there may as well not be any fast travel present for the majority of one's time in the game.
As for the combat, unfortunately I found it lukewarm. Early on you get the ability to shoot lasers at enemies, but enemies have so much health that swimming past them is typically a better solution. This gets especially annoying when you have to deal with enemies whose projectiles chase you down until you do a 180 so they disappear or crash into the wall, or have enemies who will chase you down and can actually keep up with you. Combine that with the game's lack of health items early on and it's very annoying. As a side note, using said ability doesn't really feel nice either. The attack has a very quiet noise, and enemies simply disappear when they die. It's not very satisfying at all.
The one exception to this I have is during some boss battles. Although most bosses are puzzle bosses (where you have to do a certain action to do damage to the boss), the all-out combat bosses were pretty fun! They felt like a bullet hell or SHMUP that involved both shooting endless amounts of projectiles at the enemy while dodging their deadly attacks. Honestly, it got quite intense and I enjoyed those moments a lot.
The other boss battles though...it depends. As I said above, the other ones are primarily puzzle bosses, which means they challenge you to figure out how to damage the boss or make it vulnerable to attack. No spoilers on this, but the bosses ranged from "I had to think about this for a few minutes" to "how in the world am I supposed to figure that out?". Have no shame if you need a walkthrough for these, as the clues for what to do on them are very vague.
Granted, I say all these things as someone who doesn't typically play Metroidvanias. Considering the high amount of positive reviews this game has, I imagine people haven't found these to be as serious issues as I, or disagree with my interpretation of them. Regardless, please note that if you buy Aquaria, you're going to be going into it for the atompshere and exploration, and the combat is mostly passable.
In the end, I'd say if you find the game interesting and you enjoy Metroidvanias, I'd say try it. Perhaps this game is not my typical "cup of tea", as the phrase goes.