Talk:FAQ/@comment-71.194.106.57-20120718194402/@comment-5231234-20120719015107

Yea I just unlocked the concrete walls a few days ago. Can't tell you how many is left but it seemed to come quicker than the other two did, but that could have been because I built all 3 of the hero bases 1 after another and they take up a whole dang segment themselves.