Building links should I target one main keyword or Multiple Keywords?

Hi, blackhat members

I know this question may sound stupid but I just start learning to do off page SEO...
I'm planning to build high quality backlinks to my main site through guest posting and other stuff...
should I target one main keyword to rank for, like I build a couple links to one keyword till it ranks then I move to another one?
or should I build a lot of backlinks targeting multiple keywords randomly?
my plan is to rank for multiple long tail keywords that is low to medium in competition

thanks,

Lots man.. working on just one will stick out like a sore thumb and is a sure fire way to get yourself slapped by Google.. diversity is the key.

In my long term projects and for clients now days we are actually using hardly any of the main keyword as an anchor, a few but not many! Instead I make sure the onsite is up to a very high quality, then when building links use clever titles, tags etc which have your keywords within them.. Always try to think of SEO in a common sense type of way, like how would this be happening normaly? Normally you will get anchors such as "I read about it on this site" "this interesting article" and so on, very rarely will it naturally be your keyword unless its your brands name which you should use as an anchor anyway.

But yeah never just one keyword, the more the better and the more creative you get with those anchors the better too.

Thanks for this great reply tommy