Citadel Games' Legends of Aria is an MMO designed to be controlled more by the players than by the game developers themselves. Its an open form MMO that flies in the face of what we expect from MMORPGs these days, because it is pretty much nothing like World of Warcraft. Citadel Games have a pretty specific vision for Legends of Aria which involves making sure no quests are eternal and that special events can only be played once. Basically – once you've done the thing in Legends of Aria, its done for good. Which is a pretty linear line of thinking for an online game. Typically online RPGs allow you to relive content because they survive based on replay value. With no replay value, the game doesn't fit in a live service model.
But that essentially creates a player decision vacuum.
So in Legends of Aria, the idea is to prevent that vacuum from occurring at all by giving them a sandbox style game to play around in. But this is an MMO, so it is a shared sandbox.
As Citadel Games says on their official website, "Coupling dynamic behavioral systems with real players and gods gives us incredibly rich opportunities for cause and effect. The egg you steal from a dragon today may be the reason she's attacking a town you left behind tomorrow."
Legends of Aria is also boasts a skill-based progression system, rather than a class based one, which makes it a bit unique on the realm of MMORPGs, as most stick to a strict class system, even if they might let you change that class later on down the line. So you can learn any weapon you like, pick up skills from other players, trainers in town, or by reading dusty tomes from the dungeon you're currently plundering. Once you've learned the basics of a skill, you can earn experience in it by engaging in activities related to that skill. As you advance the skill, new abilities related to it will be unlocked – like a perk system.
All that said, there is a skill cap, so you can't be a god at everything.
In addition, the game has PvP and PvE on the same servers – with certain areas being safe from PvP content, while further out into the world it becomes much more lawless. Which unfortunately means that you'll have to take the risk of PvP attacks if you want to explore all that Legends of Aria has to offer.
In their attempt to re-define MMOs, Citadel Games have had to make some compromises here and there. And that might mean the game isn't to your liking. Player houses can be dropped anywhere in the world, creating player-made villages, but that does mean you can't just ignore instanced housing districts. For housing enthusiasts it can be great, because they can drop their house wherever they like – on top of the highest mountain for that gorgeous vista, or on a lake to get beach-front property. PvE and PvP existing on the same server with location limitations will anger some players who like to avoid PvP entirely. Skill based systems are much less controversial, but they do tend to create players who want to be god-tier at everything, because they feel they should be able to. And that makes Legends of Aria more than just a game. It's also an experiment in how we play MMOs and what we expect of them.