Complex sentence: With the book, Kahlan returns to Aydindril, but a battle ensues with Drefan, and she is unable to defeat him, luckily Richard comes, and disables Drefan who is later killed by the silph.
Split into simpler sentences: With the book, Kahlan returns to Aydindril, but a battle ensues with Drefan, and she is unable to defeat him. Luckily, Richard arrives and disables Drefan who is later killed by the silph.