Harf is a public 4 way video chat: https://harf.io/
In Harf you can start or join a 'room' in which there are 4 'seats'. Anyone with a mic and a camera can take a seat and join a conversation. When you start a room you decide who takes a seat. There are no rules! Which is what makes it better than Blab that discontinued because of 'low quality' and 'harassment'. Bullshit. The complete randomness is what makes this idea so great.
The creator is a friend of mine who used to love Blab.