Sapper sends a message when you Sap or Blind a mob. Current as of patch 2.4.
The original sapper gave you lots of useless options (Battleground announcement? @_@). I've taken them out. /sapper say or /sapper party to set the announcements to the say or party channel. If you don't like the sound when you blind someone, just delete the .wav file.
The Sapper reborn Team
