She compels Matt to pick a fight with Tyler, intending for Tyler to kill him.
Elena tells Stefan that while Katherine is gone, she still doesn't feel safe and can't be with him right now. The_vampire_diares_2x07
While Caroline manages to knock Matt out to stop the fight, Katherine’s backup plan succeeds when a girl named Sarah (also compelled) attacks Tyler with a letter opener. In self-defense, Tyler accidentally kills Sarah, officially . The Final Twist She compels Matt to pick a fight with
Bonnie casts a spell on a room to trap Katherine inside with the Salvatore brothers. Tyler accidentally kills Sarah
Bonnie eventually convinces Lucy to switch sides. Lucy breaks the link and paralyzes Katherine, allowing Stefan and Damon to throw her into the tomb instead of killing her. Tyler's Transformation