Complex sentence: Unbeknownst to them, Bonnie created a spell to transfer Klaus into Tyler's body, meaning Klaus is still alive-she did this to save her friends and her mother (Persia White) who also stems from the same bloodline.
Split into simpler sentences: Unbeknownst to them, Bonnie created a spell to transfer Klaus into Tyler's body, meaning Klaus is still alive. She did this to save her friends and her mother (Persia White) who also stems from the same bloodline.