How can I flag/turn in this anonymous jerk that keeps flooding others questions?

Hover your mouse cursor near the top right corner of the answer. A flag should appear. If it doesn't, move the mouse cursor around until a flag does appear. When you seen the flag, click on it. That will open the reporting form. Down-vote the answer, check the option that the answer violates community guidelines. Use the box to write a message explaining how it violates community guidelines.

I report that idiot every single time I see their post. There is no proof it's just ONE person though because anyone can go under anonymous. Just flag all of that crap you come across then report it as spam (select the first option you see for a violation of the community guidelines).

In order to prevent this person from posting his/her rant, past the following with my questions.

Note to the anonymous yahooer who is posting the "Three Big Earthquakes" rant: DO NOT answer this question unless your answer is on topic. If you are going to post your doomsday rant, ANSWER THE QUESTION before you do so!

You are incapable of seeing, I would guess, how this sounds so much like the ravings of someone in delirium state.... I suggest you see a mental health practitioner as soon as possible BE CURSED.

I have been reporting it, as I find this type of spam exceptionally annoying. The poster is probably mentally ill, but that's really no excuse to post such idiotic drivel.

Above and slightly right of the "Comment" link is a flag button.

Of course, Yahoo is notoriously lax about spammers.

I think they like them.

But at least flagged comments won't show up in the question anymore.

The only thing you can do about it is just report them for a non-answer violation.

that guy is always in the video games section I usually report him when I see him

Click report if you like and it will be hidden. That's it. Not like yahoo will actually take any action.

Just click "report"