Locke must die! Who will kill him? Logically, it should be Jack. Recall: Jack pulled the trigger on him after Locke killed Naomi. But the gun had no bullets.
But our inside sources reveal.......it will be Walt who will kill Locke. Recall: everybody was playing golf. Walt wanders off & sees Locke throwing knives into a tree. Walt asks 'Can you teach me that?'