Logic Masters Deutschland e.V.

Back from a long and wacky hiatus, I felt like I should finish the rest of the current project that I've been leaving undone for a while. After a plenty of misses and bad mistakes, I finally finished what's probably one of the craziest projects I've experienced through there.


Following the first entry of my ABC-Box mini series, here's the second one with the idea of adding an extra grid within the main one with extra rules for interactions... but hold on, one needs to also deduce the position of that extra grid too.
In my opinions, this puzzle has multiple stages overall and I highly recommend only solving this when you're fully conscious because it's easy to make mistakes in the middle here.


The example images below will also help one to visualize how the entire thing works overall. For now, do enjoy the treat!



Rules:

Located within the 12x12 grid is a 6x6 latin square with the exact given setup, and the position of this latin square needs to be deduced. Ignoring the latin square, the remaining cells of the 12x12 grid shall be filled with letters from A, B or C so that each such cell contains exactly one letter and they satisfy the following ABC-Box rules.

1) 6x6 latin square: Each row and column contain digits from 1-6 each once. A white dot between two cells connects two consecutive digits, and not all white dots are given.

2) ABC-Box rules: For some particular row/column, a series of clues is provided for them respectively and the series implies a few things below:
- The number of clues corresponds to how many blocks of the same letter are within that row/column. No two orthogonally adjacent such blocks will contain the same letter to each other.
- The order of the clues is from left to right for rows and from top to bottom for columns.
- A letter clue indicates the letter to be filled in its respective block, and the length of that block is non-zero but actual value is unknown.
- A number clue indicates the length of its respective block that contains the same letter, but that letter is unknown.
- A question mark (?) implies that its respective block contains an unknown single letter and the length of that block is non-zero but actual value is also unknown as well.

3) Interactions:
- For the sake of the latin square, A, B and C represent three different digits (from the range 1-6) that need to be deduced. Same letters correspond to same digit and different letters correspond to different digits.
- Any letter that is orthogonally adjacent to the 6x6 latin square will act as a cryptic numbered room clue for that latin square. A numbered room clue outside a row/column shows the digit that needs to be placed in the Xth cell from that clue's respective direction in its row/column, where X is the digit right next to that clue.

NB: It's possible that some block of single letter gets 'intersected' in the middle by the latin square, see the examples below.

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Here are some example images with how the final grid turns out at first (only for illustration purpose, I just generated a random grid for like 5 mins).
[For an actual solvable example puzzle, click on this link that leads to another grid - though I feel like it's not terribly exciting.]
    

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The main puzzle:  Penpa plus  -  Sudokupad



The answer check in penpa link will trigger once every cell in the 12x12 is filled with correct number/letter. I also added an extra small table for the 'corresponding values' of letters A-B-C for the latin square. For now, good luck and have fun solving!