Complex sentence: On a mission to steal an ancient sword from a museum Sumo and several other members of the MLF ran into Cable who has been waitimg to ambush them he shot Sumo in the head, killing him.
Split into simpler sentences: On a mission to steal an ancient sword from a museum, Sumo and several other members of the MLF ran into Cable, who has been waiting to ambush them. Cable shot Sumo in the head, killing him.