A substitution cipher swaps every letter for another letter and keeps that swap for the whole message. The text still looks like text — same word lengths, same spacing, same doubled letters — it just isn't in English yet.
Word shapes survive. If you can see one- and two-letter words, an apostrophe, or the same letter doubled in the middle of a word, you are almost certainly looking at a substitution.
Caesar Shift A Caesar shift, but you have to find the distance yourself. Try the one-letter words first.
TREASURE MAP
shift unknown
XVIEWYVI QET
Every letter has been swapped for another one, and the same swap is used all the way through. Letter shapes stay put — word lengths and spacing are still real clues. This one is Caesar Shift. The key: shift unknown. A Caesar shift, but you have to find the distance yourself. Try the one-letter words first. Take the first letter, X, and walk it back 4 places: it lands on T. Do that to every letter and the message reads T R E… The answer was TREASURE MAP.
Start with the short words and the most common letter. In English that letter is usually E, and a lone letter is usually A or I. Two or three correct guesses tend to collapse the rest of the message on their own.
One a day, three guesses, and a streak that breaks the moment you miss one. Today’s is cipher #1.