User blog comment:Kogath/Monster Hunter Frontier G9 Discussion/@comment-4731324-20151118040405

http://www.mhf-g.jp/preview/g9/pc/lavi_event.html

Don't know why this hasn't been mentioned yet. It looks like parties of 4 to 8 people can hunt Berserk Laviente (Raviente) instead of having to gather 8+ or 24+. And if that info from what Ryen said below is correct, it looks like the same applies to Normal and Violent too.