Natsu, Lucy and the rest are on a mission when they get separated and meet Haru, Elie and the rest. After a bit of bonding, and fighting, they must team up to defeat and opponent.
There were some slight changes that sort of annoyed me, especially when it came to Rave. Their appearances were changed to more closely resemble the characters from Fairy Tail and in some cases, colours and details were changed for no apparent reason, such as Elies necklace, Lets hair colour, the horse/rabbit colour and Griff became a bit more jelly looking. That being said however, I’m pretty sure the Rave characters are set at a time sometime after the anime ended as there was also a couple unexplained characters added. As I haven’t read the manga yet, for all I know, the changes in the characters are explained there.
It was entertaining though. Gray was completely naked, Juvia thought Gray and Musica were making out, Elie insisted on calling Happy a bug, etc, etc. Although, it would have been a bit more interesting (in my opinion) if they had made it longer and included more of Gray and Musica fighting. I’m also sort of curious if the characters are related to each other in some way….
Anyway, I say it’s worth watching, if you like both Fairy Tail and Rave. I’d also suggest watching FT up to at least the Key of the Starry Sky arc (ep 125-150), and Rave at least to the end of the anime. If you don’t, you’ll probably be extremely confused on what’s going on. But like I said, with Rave, what’s shown here goes beyond the anime.