untested
(defun c:t1 () (vl-load-com) (vlax-for b (vla-get-blocks (vla-get-ActiveDocument (vlax-get-acad-object)))
(vlax-for o b (vla-put-color o 0)(vla-put-linetype o "ByBlock")(vla-put-Lineweight o -1)
(vla-put-EntityTransparency o "ByBlock")))(vl-cmdf "_ATTSYNC" "N" "*"))