Of a fantastically thematic and exciting expansion narrative wise, (Jeitinho has a fantastic review by ogrillion praising its impeccable naming and flavour), I find this card to be the best named of the set.
An amazing pun of the titular character's (almost) virtual nature and the term Hollow Men, both a reference to T.S.Elliott's poem and a term to describe the soulless politicians who dictate everyone's lives without empathy. We're looking at men with no substance or virtue within them, paralleled with The Holo Man having no physical form himself.
I think it paints such a powerful image! The manipulation in the flavour text for Kingmaking shows the characterisation isn't limited to the pun either.
I think Rebellion Without Rehearsal is Null Signal's best work yet.
Let me be no nearer
In death's dream kingdom
Let me also wear
Such deliberate disguises