I mean I'd be down if there was a "Purge" account or something. Not a separate world, but a status like Ironman or something where you could only attack players that have 'Purged'. Banks could be a safe-zone, and trading, etc would be allowed, but you'd only be able to attack other players that have 'Purged' and would be no limitations as to where outside of specific safezones.
IE a Purged player couldn't attack a normal main, ironman or HIM, only those who have purged. Making it an event wouldn't work well as too many players don't PVP and would get angry upon being attacked and or losing items.. if it's a choice, I'd be all in support.
I would definitely make a Purge account - with rules where you can't bank for 5-10 minutes or w/e after getting a kill or skulling. Could be fun!