So during the crucible I stumble across warlocks who instantly kill me with their melee, specifically the life drain one. But when I use my deadlock with the life drain perk it's takes only half of their health. Why is that? What is the secret to getting an instant melee kill? <<[EDIT]>>: The man was not wearing a ram. There was no lag at the time either. Everyone in the lobby was in the green zone. Aside from that this was not the first encounter... <<[EDIT#2]>>: Thanks everyone for the replies. Learned a lot about both classes. But there were probably many or little possibilities on how people were able to land a successful instant energy drain kill. But thanks again guys.