After creating and inserting a block, you may need to modify the individual components of the block definition or the color and linetype properties of a block reference.
If you need to modify one or more objects within a block separately, you can disassemble, or explode, the block into its component objects.
Modifying a Block Definition
Modifying the Data in Block Attributes
Changing Block Color and Linetype
Disassembling a Block Reference (Explode)