Ciel in Wonderland (Pt. 1 & 2) - As you may have guessed, this is the Alice in Wonderland story with a Kuroshitsuji twist. Ciel is Alice, Sebastian is the rabbit and... well all of the other Kuroshitsuji characters are included as well. Its good for some laughs and they're definitely not like any normal episodes.
Welcome to the Phantomhives - I didn't really expect much out of this episode but it was surprisingly like a typical Kuroshitsuji episode except from a first-person point-of-view. Elizabeth is invited to a ball at Ciel's mansion and invites her friend (presumably, you) along with her. A plot unfolds and without giving anything away, its a pretty satisfying episode.
The Making of Kuroshitsuji II - Like Ciel in Wonderland, this one is good for laughs. This takes you behind the scenes of the show, and presents the whole crew as actors instead of their roles in the show. It seemed a little odd at first but then it got pretty funny and charming.
The Tale of William the Shinigami - In case you wondered about Grell and William's history here is the episode that explains just that. Its a story about Grell and William's first mission as shinigami, as well as introduces you to what goes on behind the scenes of becoming a shinigami. I enjoyed this episode because of how it developed these characters further and expanded on your knowledge of the shinigami world.
The Spider's Intention - Basically an episode introducing the Trancy butlers in more details. This episode was pretty cool since it told a little more about the triplets than what the series showed.
