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There is no regular stuff now in Sydney and as far as I know, Melbourne. It's all either alternating nights and/or monthly events.
Melbourne has a few goth venues operating on a cycle, but no pubs are dedicated to the genres
Because its so hard to timetable events, the best way to figure out what's happening in Sydney and Melbourne is thru street press found in almost all music stores and/or joining one of the multitude Aussie scene of cyber groups