The Blame lets your teammates to punish griefer after the blame vote.
1.find player X griefing your base.
2. write BLAME! X griefing
3.let your teammates to vote yes.
4.now you can punch that X griefer with your shovel, blinding him with his helmet(he sees only a line of pixels in the lowest part of the screen) and dealing 5 damage each hit of a shovel for 5 minutes! No, you cannot shoot him,this is a punish, not a slaughter.