Describing Titans Annual #1 as Cube with superheroes - while an apt summary - would do it a disservice. Dan Abnett's script is far more than that, playing off of Abnett's knowledge of their characters and the reader's uncertainty as to just how things stand between these characters in the Rebirth reality. In this, Abnett is able to define another piece of the lost lore of the Titans while spinning a riveting tale and making use of an underused villain I was quite pleased to see return.
And yes, it must be said, we do discover Donna Troy's origins in the Rebirth reality here. It's something wholly original (as far as I know) and rather fitting given the changes to Diana's background in The New 52. More I will not say beyond this issue being a must read for any Wonder Girl fans out there.
The artwork for this special is outstanding. Minkyu Jung does a fine job of keeping the story moving visually - no small feat given how much of the story is the characters just talking! The use of light and shadow is particularly impressive and the colors by Adriano Lucas are perfectly chosen.