Here is a link to a youtube video I did for a guitar lesson site a few years ago. I will be posting more. It's a harmonic minor lick. The tonal center can be A but other options exist such as E Phyrgian Major. 

A good time to use this lick is when playing over an Am (a c e) chord or an AmMAj7 (a c e g#). To create an even cooler sound use it over the E7 (e g# b d) chord or an E7b9 (e g# b d f). When you get the lick down play it over a backing track in A minor. After you are comfortable with it move the lick to all keys.

Try it slow and have fun. Then go to the local music store and blast it out. 

https://www.youtube.com/watch?v=EETmrANwRcg