Several times in the history of the MSmg stream, there were incidents where a stream owner would go rogue, demote all the other stream owners then remove all the stream Moderators, then self delete. Sometimes as a parting shot before deleting they would turn the submissions per day for the stream to zero.
After the first few times that happened, there was a user account named arkuum that popped up in MSmg, threatening that they were going to do it again on a specific date, but the date came and went with no incident, the account self deleted and almost slipped into obscurity. The name arkuum for this particular type of sabotage was coined and did stick after that though.
One safety mechanism the site has built for ownerless or abandoned streams is that any Global or Community Moderator can claim ownership and restore things. The sitewide Moderators have intervened this way in MSmg many times.