Not that there's anything too familiar in these books. Butler's original and complex society of Oankali captivated me from the beginning. I liked the biological twists and the cultural ramifications, both in the Oankali themselves, and in the ways humans and Oankali came together. The resistance, the acceptance, the blending, the numerous possible outcomes of the genetic mixing, were all involving at both the level of society and at the individual character levels. I found the construct characters fascinating and enjoyed how the characters in the first book didn't fade from view, because I cared about them too.