Complex sentence: Missy tricks Clara into setting off a security camera and then handcuffing Clara to the camera as bait for the approaching Dalek so she can punch holes in the Dalek casing so the deacying Daleks climb into the casing as revenge for being left and kill the Dalek.
Split into simpler sentences: Missy tricks Clara into setting off a security camera and then handcuffs Clara to the camera as bait for the approaching Dalek. She punches holes in the Dalek casing, and the decaying Daleks climb into the casing as revenge for being left, killing the Dalek.