There are tons of hidden HN features unlocked at different thresholds. https://github.com/minimaxir/hacker-news-undocumented

501 karma for downvoting

Oh wow. I lurk 99% of the time, so I doubt I'll ever reach those heady heights. Thanks for the link, though!

Yeah. Once you’re above a certain level of karma points you can downvote.

I can downvote but rarely do it. Also a comment can only be downvoted 4 times. After that downvotes are not counted anymore if I remember correctly.

I've had comments voted lower than -3 (you start at 1) plenty of times. My favorite one is one comment criticizing Microsoft that oscillated from 25 to -10 a few years back (yeah, I refreshed this one quite a lot to see how it changed, that was fun).

But I don't remember anything lower than that recently, so it can be a new change.

5 times, the lowest you can go is -4.

You’ll get the ability to downvote when you reach about 500 karma.

Only for the 1%