Aquaria tells the story of Naija, a water-breathing humanoid female who's apparently lost her memory and must wander a series of underwater passages to piece together the clues of who she is and was. Voiceover narration in video games is famously spotty, and can take you right out of immersion if it's badly done, but in this case, the voice of Naija is calm, nuanced, and definitely adds to the almost somber atmosphere of the title.

The game spends its time underwater, and the animations duly reflect this. There is a nice sense of weightlessness and drift to Naija's movements, which you control by WASD, or by moving the mouse around and either holding down the left mouse button, or the Space bar. The farther away from Naija you hold the cursor, the faster she swims; holding the cursor directly over Naija will make her stop swimming. She also has a tiny speed boost that activates when you click the mouse button at a distance from her; this is useful for escaping enemies that are hot on your webbed heels.

Naija can also look around the area without moving, which is activated by holding down the Shift button, and can cling to walls, floors, and ceilings to anchor herself when riptides threaten to bear her away.

The key element of gameplay, though, is Naija's Song. Centering the cursor and holding down the Control key will activate a menu of eight icons arrayed in a circle around her. Each icon, when the cursor passes over it, emits a different musical note, and each icon has its own color. As you progress and explore the environment, you'll come across a number of plants rooted in the rocky surfaces of the environment. Each of these plants will have a bulb corresponding to a color of one of the eight icons. By floating near a bulb and "singing" the proper note, the bulb will open, releasing an item for Naija to collect. It might be a leaf, a piece of meat, a bulb of oil, or any number of other organic items. And here's where it gets a little more engaging.

Hitting the Escape key will open Naija's inventory, where you can see and arrange the item's you've collected. The items can be combined to create new items, each of which confers a benefit: you might put an oil bulb together with a piece of meat and "cook" it to create "Hot Soup", which gives you a boost to your traveling speed for 30 seconds. Each of these combinations is known as a Recipe, and you'll discover new recipes as you journey through the game.

There are four sections to the inventory screen: Recipes and items, Pets, Special Items, and Songs. We'll pay some attention to this last one next.