Talking in Inverted Alphabet brings me much alien euphoria!

A=Z B=Y C=X D=W E=V F=U G=T H=S I=R J=Q K=P L=O M=N

Example: R zn zm Zorvm = I am an Alien.

Dsl dzmgh gl gzop rm Rmevigvw Zokszyvg drgs nv?