There’s a lot going on the the world of Kingdom Hearts, so you may need to have a lesson in history before the next game comes out. If it’s been a while since you last played, don’t worry: this new trailer for Kingdom Hearts 2.5 ReMIX will tell you everything you need to know before diving into the next game.

Kingdom Hearts 2.5 ReMIX is a HD version of Kingdom Hearts 2 on PS2, and continues the story of the first games, which you may have played in Kingdom Hearts 1.5. The ReMIX version contains HD versions of Kingdom Hearts 2, Birth by Sleep, and the fancy cutscene films from Re:Code. Playing both Kingdom Hearts 1.5 and 2.5 will mean you’re ready to play Kingdom Hearts 3, which will hopefully be released soon.

The Kingdom Hearts 2.5 ReMIX release date is December on PS3.