- Hides whispers from players below a specific level.
- People on your friends list.
- People that are part of your guild.
- People above the level you choose.
- People you've whispered since you logged on.
Simply, if a "bad" person whispers you, the whisper is blocked (hidden), then you automatically send them a whisper (also hidden) of what level they must be for you to see their whispers.