REFEDIT command
Edits block references and externally referenced drawings.
Icon: 
Description
Edits the selected block reference or externally referenced drawing. The Reference Edit dialog box displays after you select a block. You can use the REFCLOSE command or the Ref Edit toolbar to end the reference editing session. The XFADECTL system variable sets the fading the rest of the drawing when editing an external reference or block. Values between 0 (no fading) and 90 are accepted. If the XEDIT system variable of the selected external reference is 0 or OFF, a dialog box displays the message that you cannot edit the selected xref block.
Note: Only one reference can be edited at a time.
Note: The HIDEOBJECTS, ISOLATEOBJECTS, and UNISOLATEOBJECTS
commands are enabled.