THE REVEAL unmask a cell with the same key that hid it
To reveal a hidden cell is to apply the key again: 1 ⊕ 5 = 4. Because XOR is its own inverse, the operation that hid the value is the very operation that reveals it — reveal is not a different mechanism but the same one, run a second time. The masked 1 gives nothing away; the key turns it back into 4. This is the mirror of dart 330, and the tightest palindrome in the batch: hide ∘ reveal = identity, an operation that undoes itself. Concealment and disclosure are one act seen twice — the going-in and the coming-out collapsed into a single, self-inverse gesture.
THE TECHNIQUE unmask: hidden ⊕ key = original (the same XOR)
The demo reveals the masked core with the same key — and it returns to 4: live demo
HISTORY & CREDIT the Vernam cipher / XOR unmask · 1917
“Decryption is the reverse of encryption.” — for the XOR mask it is the same operation: the key that hid the value reveals it. One gesture, its own undo. cited
1917–19 · Gilbert Vernam — XOR encrypt and XOR decrypt are the identical operation. self-inverse · (x ⊕ k) ⊕ k = x: reveal is hide, applied again. mirror · dart 330, the hide: mask and unmask, one act twice.
The masked 1 becomes 4 under the same key that made it 1. To reveal is to run the hiding backwards by running it forwards. Vernam, 1917
RECOMMEND FOR I-13 the unmasked cell, on the compiler
On the canonical compiler, revealing the masked core (1) with key 5 returns 4:
$ i13 run d_reveal.i13 # hidden ^ key
RUN OK · 12 step(s) · peak stack 2 · call depth 0
hidden = 1
revealed = 4 -- the same XOR undoes the hide: identity
Recommend, honestly not a keeper: the reveal completes the hide's self-inverse pair — and self-inverse is precisely the CRC/Verlet keeper the corpus already holds, so this opens no new axis. What it gives the batch is its purest palindrome: hide (330) and reveal (337) are a single operation whose double application is the identity — the clearest instance of the law every pair here obeys, that going in and coming out cancel.