Email blocking

Lately I have been getting junk/spam on a daily basis from a domain that ends in .blah blah blah (not the real name) but every day what precedes that changes. in other words it's like today it will be *** Email address is removed for privacy *** and then they will change everything preceding the "." and send more junk. This is actually happening several times a day. I delete and tell the "new improved" hotmail client to block all future emails but it's no help because of the constant change. I attempted to do a wildcard but the blocker wouldn't take it.