Brain Out Level 104
📝 Walkthrough
Overview
The prompt presents a letter pattern: if CDE equals EDF, then EFH equals what? An Enter field and an OK button sit below the question, with no objects to move. The puzzle asks you to infer the transformation applied to the three-letter group and apply it to EFH. Once the rule is read from the first example, the missing three-letter group follows directly. The answer is HFI, entered in the field and confirmed with OK.
- Difficulty: Regular
- Estimated moves: 1
Step-by-Step Solution
- Read the example carefully: CDE maps to EDF. Write the three input letters in order as C, D, E, and the three output letters as E, D, F.
- Compare the positions. The middle letter D stays in the middle of the output. The last input letter E moves to the first output position, and a new letter F, which comes right after E in the alphabet, fills the last output position.
- State the rule in words: take the third letter first, keep the second letter in the middle, then append the letter that follows the third letter in the alphabet.
- Apply the same rule to EFH. The input letters are E, F, H.
- Move the third letter H to the first position, keep the second letter F in the middle, and append the letter after H, which is I.
- Combine those three letters: H, F, I, giving HFI.
- Tap the Enter field, type HFI, and press OK. The level accepts HFI as the transformed group and shows the success panel.
Strategy & Reasoning
Letter puzzles like this are solved by matching positions rather than guessing an alphabetical shuffle. The example keeps one letter fixed in place, which reveals that the middle position is preserved. The other two positions are not a simple reversal: the last letter moves to the front, and the trailing output letter is the alphabetical successor of that moved letter. Writing both groups side by side makes this structure visible.
A common wrong turn is to treat the mapping as a full reversal, which would turn EFH into HFE, or to continue the alphabet blindly. Neither matches the CDE-to-EDF example, where the final F is new rather than the original first letter C. Checking the rule against the known example again before applying it to EFH confirms the middle letter stays put and the successor letter goes last. The resulting HFI is the only group that satisfies the same transformation.
Tips & Common Mistakes
- Keep the middle letter in the middle; in EFH that means F stays as the second letter of the answer.
- Move the third letter to the front (H first) and add the alphabet letter after it (I last), rather than reversing all three letters.
- Enter HFI and confirm with OK; if a reversed or alphabetized group is rejected, re-derive the rule from the CDE equals EDF example.