Since I don't know the exact 'black and green dragon story', the main characters would likely be the black dragon and the green dragon.
As I don't know the exact 'Black Dragon Story', it's hard to say the main characters. But generally, aside from the black dragon itself, there could be a hero who tries to either defeat or befriend the dragon.
Since I don't know the specific story, it could have a brave knight as one of the main characters who is determined to face the black diamond dragon. There might also be a wise old wizard who gives advice on how to deal with the dragon.
I'm not sure which specific 'black and green dragon story' you are referring to. There could be many stories involving black and green dragons in different mythologies or fictional works.
The main characters are Green Arrow and Black Canary.
Most likely, the black knight is one of the main characters in 'Black Knight Dragon Story'. He would be the one taking on challenges and showing heroism. And of course, the dragon is also a main character. It could have unique abilities like flying and breathing fire, and it might be a key factor in the knight's adventures.
Vegeta could also be a main character. He's Goku's rival and often teams up with him to face powerful enemies. Maybe in this 'Black Story', Vegeta has some new development in his power or character arc related to the 'Black' aspect of the story.
I'm not sure exactly who the main characters are without more information about 'the green book story'. But it could be a young adventurer who discovers the green book.
The main characters are the green children themselves. They are strange and unique in that they are green - hued, which sets them apart from the normal humans in the story.
Since I'm not familiar with this story, I have no idea about the main characters. It could be a story about a person named Faith Green, in which case Faith Green would be a main character. But without more information, it's all speculation.
It's hard to say for sure without reading it. But it could be the black dragon itself as a main character, or perhaps a brave knight who is set on breaking the curse.