Best you can do is "Report to moderator" Provide them with the proof of Ban evasion.
This troll has been reported three weeks ago with
this reference, and report was marked as Good, however korner continues to comment on the forum.
Next to deal with the self moderated topics - Create your own topic for real discussion to happen in without fear of the entire thread being wiped. That's exactly what the warning at the top says to do. Ideally the troll will starve with no attention.
Many people in the Russian section don't guess that one of the members usually erases his threads, so they're trying to make a constructive conversation. But unfortunately all their comments sooner or later end up in the trashcan.
P.S. It would be great if moderators or administrators could restore topics after such abuses and disable the self-moderated option in them. Option of self-moderated was created on forum clearly not for mass destruction posts.
I think that Self-moderated option should be disabled for new threads at the main page of the Russian locale, just as it was done in Meta.