Originally posted by: RamLakshman
Valmiki wrote Adbhut Ramayana to highlight events that were left out of the main epic. Ramayan was written to glorify the character of Sri Rama. However, he left out events that would have glorified Sita at Sri Rama's expense. Adbhuta Ramayana is a feminine narrative that highlights the significance of femininity. (It's called "Sakta" version which translates to Shaktism = devotion to female deity).
Adbhuta Ramayana begins with Rama's confrontation with Parashurama as he and his family returned from his wedding in Janakpura. The story glosses over other noteworthy events of the epic, focusing more on supportive stories intended to elaborate upon the major themes of Valmiki's primary work. Everything before that, Tadaka vadh, dhanush breaking - everything is omitted.
The climax of the book is when Lord Ram prays to the cosmic Goddess or Shakti. He tunes 1008 divine names or mantras which describe and enumerate the various glories virtues and attributes of the magnificent Shakti of Mother Nature.
This book has Sita killing Sahastra Ravan, on the battlefield itself right after Ram kills Ravan. That's where she takes Mahakali roop.
I hope this helps, Pete! 
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