I would only like to be able to fill cell B2 with values "x", "y", OR "z" only if A2 is filled with any value.

I have come up with a solution, but I don't like it. It's very long. Currently I have this Data Validation in B2: =OR(IF($A2<>"",$B2="x"),IF($A2<>"",$B2="y")).

The problem is that I have 32 unique "xyz's". Could I do anything with a named range? My attempts thus far, have not proved fruitful.