So I want to know how to play/make like metalcore and deathcore solos for my band. I want to add some tech and not just be breakdown after breakdown like every other core band. Kinda like volumes, parkway drive etc. I know how to make rythmns and riffs pretty well but I just dont understand the concept of making a solo, so my exact question here is what scales do I need to know or learn to make a metalcore/deathcore solo. Cause all I really know is that I need to know some scales, but I dont know which, and how should I apply a scale to my writting?

some examples of what aiming for would be-
http://www.youtube.com/watch?feature=player_embedded&v=ABCOHgrqX14#!
http://www.youtube.com/watch?v=zx3IWEzvHAw

Thanks to anyone who is willing to help :] oh and if you have a website where it shows the scales you mentioned would really help alot too.