Kingdom Hearts χ has many notable differences from other games in the series. Story-wise, the game predates the most pivotal event in the game's lore, the Keyblade War. The rest of the franchise takes place in a setting after the Keyblade War, so Kingdom Hearts χ served to fill in the gaps of what happened before the main Kingdom Hearts games. It is also the first and only game in the Kingdom Hearts franchise to feature multiplayer, where players create their own character and train to become Keyblade Masters. Players are led on missions to defeat the Heartless, the main antagonist "faction", and as the story progresses, they slowly discover that there is a sinister plot involving the Keyblade Masters.
Kingdom Hearts χ was originally developed as a Japanese browser-based game in 2013, receiving a port to mobile devices as a Japan-exclusive over two years later, under the new name Kingdom Hearts Unchained χ. After heavy demand, the game is getting a westernized release and a full port to North America on April 7. The game is free-to-play, though there are optional microtransactions that will allow players to progress more quickly if purchased.
Although Kingdom Hearts 3 - the long-awaited conclusion to a series that so many grew up playing - is still a ways off, Kingdom Hearts Unchained χ will act as another pastime for fans of the franchise who have patiently waited all of these years and it may even rekindle the love for the series that some have lost with the lack of Kingdom Hearts 3.
[Source: Square Enix]