The Guardians of Zork

1. The Guardians strike anything which they see between them.
2. The Guardians are described as "identical" and "perfectly symmetrical." If you walk in front of them or throw something in front of them, they destroy "in perfect unison."
3. Do you think a Guardian could distinguish between the sight of the other and the sight of himself in a mirror?
4. You can travel past them inside the mirror box. ("It's all done with mirrors.")