It’s an interesting group as well as phrase!
The premise is that a member makes a post featuring one of their personal opinions, an opinion that they are prepared to defend until (metaphorical!) death.
eg:
Hill: Transwomen are men, humans cannot a change sex.
and then the group members post in the comments as to whether they agree (and will join the initial proposer in dying on their ‘hill’)
So the comments read stuff like
‘Dead’
’So dead I’m dust’
’Deader than flares’
or the ever popular ‘Facts aren’t Hills’.
People who comment ‘Alive’ can either present their own counter argument or be questioned on why they don’t agree
Some people will go with ‘comatose’ if they mostly agree but have a small point of difference.
You can also start a ‘Side Hill’ (eg ‘Side Hill: Labour cannot expect to win the next GE with a leader who thinks some women have penises’)
It’s a proper weird group because it brings together the kind of blue haired teens who bang tambourines at KJK, Manosphere MGTOW Andrew Tate fans, proper old school middle aged liberals who believe in full debate and loads of terves of all ages and nationalities.
There are quite a few posters in various African and Middle Eastern countries who debate BLM style antiracist activists from the US.
There are a handful of posters who cosplay multiple identities, sock puppet style.
It’s fun because there is almost no moderation, which means the blue haired kids can’t just report and censor stuff they don’t like and the Manosphere MRAs melt down into puddles when terves get higher like/love reacts than their sexist opponents do.
Because it’s FB you can block any posters that post repetitive hills on a topic that doesn’t interest you, but it’s better if you block as few people as possible because it’s interesting to realise that while you vehemently disagree with Poster A on topic Y, you end up ‘fighting on a hill’ beside them on topic X.
Because Facebook doesn’t function in the way twitter does you don’t get the same ‘pile on’ effect (twitter works like a snowball gathering size but closed FB groups are only visible to group members and unless you go into the group on purpose you only see occasional posts from it on your news feed, selected by the algorithm).
I use my real name on FB but have my profile locked right down (and won’t lose my job over internet stuff anyway) but it’s probably safest to use an alt account.
Some threads are about pizza toppings, some are about mass shooters. It’s wild.