Complex sentence: Cassie has little time to process this information until she was killed by the "Salem Stalker" (a mind controlled Marlena) Cassie's whose body was found with multiple stab wounds in a Thanksgiving pinata.
Split into simpler sentences: Cassie has little time to process this information until she was killed by the "Salem Stalker" (a mind controlled Marlena). Cassie body was found with multiple stab wounds in a Thanksgiving pinata.