Forgive my tardy reply.
I've got it to this:
perl -e "system(mystring =~ tr/a-z/x-za-w/r)"
Where `mystring` is a hard-coded string.
So I have a working solution, but is there anyway to obfuscate it further?
To answer your question, I should have been honest from the beginning. I wanted this one-liner to do something cheeky... it's in a section of the README of the software I'm working on, as a treat for the dedicated reader.

In reply to Re^4: One-liner to rule them all... by fosskers
in thread One-liner to rule them all... by fosskers

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