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# [APL (Dyalog Unicode)], 31 bytes

<!-- language-all: lang-apl -->

    ⎕←↑(14↑(2⌷x),⍨⌽)¨,\1⌷x←⍉13 2⍴⎕A

[Try it online!][TIO-kpuasy74]

[APL (Dyalog Unicode)]: https://www.dyalog.com/
[TIO-kpuasy74]: https://tio.run/##SyzI0U2pTMzJT////1Hf1EdtEx61TdQwNAGRRo96tldo6jzqXfGoZ6/moRU6MYYgEZCa3k5DYwWjR71bgHoc//8HAA "APL (Dyalog Unicode) – Try It Online"

Lot worse than the BQN answer.

```
⎕←↑(14↑(2⌷x),⍨⌽)¨,\1⌷x←⍉13 2⍴⎕A
                              ⎕A ⍝ String of uppercase letters
                         13 2⍴   ⍝ Turn that into a matrix where the
                                 ⍝ first column is ACE... and the second is BDF...
                        ⍉        ⍝ Turn those columns into rows
                      x←         ⍝ Assign to x
                    1⌷            ⍝ Get the first row ('ACE...')
                   ,/            ⍝ Prefixes of that
                  ¨              ⍝ Map each prefix:
                ⌽                ⍝ Reverse it
              ,⍨                ⍝ And prepend it to
          (2⌷x)                  ⍝ The second row of x ('BDF...')
       14↑                       ⍝ Keep the first 14 letters
   ↑                            ⍝ Make it a matrix
⎕←                              ⍝ Print it (not totally necessary)

```


# [APL (Dyalog Unicode)], 33 bytes

<!-- language-all: lang-apl -->

    ⎕←↑(⌽⍳13)(14↑↓)¨⊂↑,⍨∘⌽⍨/↓⍉13 2⍴⎕A

[Try it online!][TIO-kpuatp0n]

[APL (Dyalog Unicode)]: https://www.dyalog.com/
[TIO-kpuatp0n]: https://tio.run/##SyzI0U2pTMzJT///qG@qp/@jtgkGIBaQftQ2UeNRz95HvZsNjTU1DE2A/EdtkzUPrXjU1QRk6zzqXfGoYwZYxQp9oMyj3k5DYwWjR71bgPod//8HAA "APL (Dyalog Unicode) – Try It Online"

Requires zero-indexing.