Cipher methods Symbols
Standard Galactic Alphabet
The Standard Galactic Alphabet (often abbreviated SGA) is a monoalphabetic substitution in which each Latin letter A–Z maps to a unique straight-stroke glyph. Designed in 1991 by Tom Hall for Commander Keen IV: Secret of the Oracle (id Software), it found a second, much wider life in 2011 when Mojang reused it for the inscriptions on Minecraft’s enchanting tables — where thousands of players manually decoded the runes only to discover that the displayed words are randomly drawn from a Minecraft-wiki word list and have no effect on the actual enchantment.
It’s now one of the most recognisable substitution alphabets in geek pop-culture, alongside Aurebesh (Star Wars) and Klingon pIqaD (Star Trek).
How does the Standard Galactic Alphabet work?
Pure letter → glyph substitution, no key: the table has been public and fixed since 1991.
- 26 distinct glyphs for A–Z, all built from straight strokes (vertical, horizontal, diagonal segments) — no curves, no loops. The aesthetic makes the alphabet easy to draw by hand and gives it its iconic “high-tech” look.
- One extra glyph for the period (
.) — the only punctuation included in the original alphabet. - No letter merges (unlike Templar or Theban): each of the 26 letters has its own dedicated glyph.
- No digits or other punctuation in the canonical version.
Historical and modern use
- 1991 — Commander Keen IV (id Software). Tom Hall designs the alphabet to dress the Gnosticene Ancients world; some in-game signs hide messages waiting to be decoded.
- 1991-1996 — Commander Keen series. The alphabet shows up in episodes V and VI, then in later id Software games (Wolfenstein 3D, Doom) as quiet easter eggs.
- 2011 — Minecraft. Notch (Markus Persson) ships enchanting tables with SGA inscriptions. The community decodes them within hours, then realises the phrases are picked at random from a wiki word list unrelated to the actual enchantment.
- 2010s-2020s — Pop culture. The alphabet keeps appearing in fan-fiction, t-shirts, tattoos, and is widely used as a teaching prop to introduce children to cryptography.
Neighbouring alphabets
- Aurebesh (Star Wars) — alphabet of the galaxy far, far away; 26 glyphs, more curved than SGA.
- Klingon pIqaD (Star Trek) — angular alphabet with 25 letters (Z absent).
- Pig Pen / Freemason — older geometric substitution (18th c.) on a 3×3 grid + X.
- Tic-Tac-Toe — Pig Pen variant on three 3×3 grids.
- Templar — another medieval geometric substitution, 25-letter alphabet.
What are the weaknesses of the Standard Galactic Alphabet?
- Monoalphabetic substitution: instantly yields to frequency analysis as soon as the message exceeds a hundred letters.
- Public, famous alphabet: the table circulates on the Minecraft Wiki, dCode, and dozens of YouTube tutorials. Any amateur cryptanalyst recognises the glyphs at first glance.
- No key mechanism: the cipher cannot be personalised.
It’s an excellent alphabet for playful puzzles and a beginner-friendly introduction to cryptography — not a security system.
The 27 glyphs
Full A–Z alphabet plus the period. All 26 letters have their own glyph — no merges.
Punctuation glyph
