A terrific game that allows up to 4 people to play.

I wouldn't recomend it while playing on your own though since that kinda defeats some of the purpose. Unlike other ARPGs or whatever we call these it's not focused around finding gear and leveling up. Instead each stage has a mission, a purpose. These are simple puzzles or annoying challenges that you need to find a plan on how to solve. It could be lasers, or bombs or just a simple "kill everything mission". After a mission you are returned to a "world map" inbetween missions. You may change between 4 classes and 2 people can't be the same class. The classes act a little different and are good for different things.
In each mission you can earn 3 crystals, which is basically the leveling up system of the game. Once you reach a certain number of crystals you unlock additional skills you can use instead of the basic ones. How do you earn the crystals? It's a little different depending on the mission but mostly it's about clearing the mission within a certain time frame, not taking damage or doing something fancy.

Great game, but play with some friends.

A terrific game that allows up to 4 people to play. I wouldn't recomend it while playing on your own though since that kinda defeats some of the purpose. Unlike other ARPGs or whatever we call these it's not focused around finding gear and leveling up. Instead each stage has a mission, a purpose. These are simple puzzles or annoying challenges that you need to find a plan on how to solve. It could be lasers, or bombs or just a simple "kill everything mission". After a mission you are returned to a "world map" inbetween missions. You may change between 4 classes and 2 people can't be the same class. The classes act a little different and are good for different things. In each mission you can earn 3 crystals, which is basically the leveling up system of the game. Once you reach a certain number of crystals you unlock additional skills you can use instead of the basic ones. How do you earn the crystals? It's a little different depending on the mission but mostly it's about clearing the mission within a certain time frame, not taking damage or doing something fancy. Great game, but play with some friends.