I am wondering that what are benefits of negative seo
I know because I run the 1st page results through a link checker and if only my site was spammed with kwkwkwkwkwkw I am certain it wasnt some page 2 guy...Yeah I see your point. But how do you know it wasn't some guy on the 2nd or 3rd page that happened to try and hit everyone on page 1 with neg SEO so that he could move up? Or maybe if you're at #5, one of the guys in the top 1-4 spots hit your site because they saw you moving up the ranks and didn't want to lose their position in the future? People can draw pretty good conclusions as to who hit them, but at the end of the day, there is nothing that gives concrete evidence as to who it was.
Most of the people that throw Negative SEO campaigns at someone and see the site drop only to reappear higher weren't doing it correctly in the first place. There's a lot more effective methods than just blasting someone with a bazillion blog comments.
Negative SEO is always dead with the passage of time due to the Google huge invention called Google Disavow, but still if you're interested in this then according to me, fiverr services are good for some good negative seo, or use automated software's who create or makes the 10000 of backlinks within an hour. In which Scrape Box, Xrumer, EWP, and other automated soft are at top of the list.
As for me, i think it's a grey area with this stuff. If you have a pretty high quality site and focus on building quality links, and some asshole comes along with a shitty emd 1-page wordpress blog and outranks you, then i say blast his site to nowhere.
The self righteous, bullshitting, "just as black hat as everyone else only 1/10th as effective" twats at SEOMOZ actually invited people to spam them as hard as they liked (and many people did) multiple Xrumer servers, SB's the works...all that happened was some of the long tails dipped then recovered to even higher positions than before.