I understand it but realized I haven't knowingly seen it. Are there any good examples of Reddit or HN comments that are not genuine? I don't do "posts", but do

I understand it but realized I haven't knowingly seen it. Are there any good examples of Reddit or HN comments that are not genuine? I don't do "posts", but do participate in comment sections / conversations, and would like to see some examples of conversations where one party is confirmed to be a bot or troll.