Besides me having a hard time with the final boss right now and my fingers are sore from the attempt....this is wonderful indie of a game.
I would I describe this game other then its a fantasy, adventure and side scroll(or rather side swimming) shooter. You control Naija, a mermaid like girl who lives in a fantastic world under the surf and who lost her memories and is compelled to go explore the world beyond her home waters after she receives visions of a boy plunging into the surf.
Gameplay wise its side scrolling swimming with shooter elements as after you get the energy form your main form of attack after hostile sea life. In addition to the shooter aspect the half of the game is exploring and solving puzzle....the underlining theme is in this world is bound by a force called the "verse" so Naija can sing different musical notes to affect the environment which can rang from opening flowers, performing a tune to change forms or solving musical puzzles. Naija as she progresses further can transform into various different forms like the energy shooting Energy Form or the plant or sprouting Nature form. Aquaria is full of hidden secrets beyond the main game story line.... collecting souvenirs for Naija's home or wardrobe, hidden mini bosses (Giant Jellyfish!!) with their own rewards (ex pets) for defeating them or unlocking new recipes. As previously stated Naija can cook different recipes which have different effects like healing. The more complex the recipe....the complex and beneficial the effects will be.
The look and feel of the world of Aquaria is where this game really shines....this is a complex under water world where various different civilizations have due to some disaster all which revolve around force destroying or driving the deity of each civilization mad....or the civilization ruined itself. The civilizations Naija explores are diverse which range from the ruins fallen mythological kingdoms, the polar north or a abandon mechanical society of automated devices and water bubble floating high towards the sun. Once Naija defeats the deith of a civilization...she narrates the history of that particular civilization and how it came into ruin. The vast different fauna of this strange world are just as vast. Some creatures like eels are friendly towards Naija while a great many others like really nasty seadragons (its a type of sea horse) want her for lunch.
Is this game worth it....for its vastly imaginative world I would say yes.