I actually get this quite often, where my client is dead, but I can still hear everyone on the server, and talk to everyone. The screen is just frozen, I can't move, and I appear 'lagged' to other people. This can be fixed by hitting the person that's client lagging with a wand if they trust you, or a destructo wand by an admin. This is a thing that happens in blockland, hence the default 'fix' function in the wand.