what do you mean by how many of advent children. There is a collector's edition if that's waht you mean??????
There was also ff: the spirits within, but that wasn't based off any of the games to my knowledge.
And then you have the animated last order, but that's a different thing based on the cloud/zack story from ff7.
Anyways, i will say I liked advent children. Not so much on the story, but more for the great battle sequences. Cloud vs. Sephiroth, mmmmmmmmmmmm.