Battle Double

You create a shadowy double of yourself that superimposes itself on
you. As a bonus action, you can move the double up to 20 feet away from
you; you can then use it as the source of any weapon attack you make or
spell you cast, as if you were standing in the double’s spot. At the end of
your turn, the double returns to your space.

The battle double can’t be damaged or even attacked. It has no real,
physical presence except in the moment when it attacks.