I drew these two original concepts in about 1 hr total. they are still a work in progress.
To make these
I first started with a big brush and roughly painted in some darks with no real idea of what i was going to make (i did think dogs as a theme would be cool).
Then i used a big brush and roughed in some darks for where armor may go. Then i roughed in some pen and soon moved to the second concept. I repeated the same kind of flexible flow. For example here i felt the need to move to a new concept and i let it happen instead of forcing to stick onto one idea.
Then i tried something a little different i opened up a new photoshop session and pasted in one of the two silhouette concepts. Then i lowered the opacity and roughed in some pen. Then roughed in some darks (i'm still a beginner in photoshop but i think can use the darken and lighten modes with brush to color on same layer). Also i found it helpful to group all the layers of the rough silhouette pass so as to get kindof like a clean start in the new file.
This kind of very flexible flow was very fun although as you can see the sketches are far from finished but the fun in creating these "fantasy dogs" was awesome.
Hope you enjoy.