Looking at the middle of the string you can see 5kce5n9g4u which could point to the prefix and suffix but then the rest doesn’t really look good.

There are 18 characters, try reversing the first and last groups of 9 characters

5eck5ayze1863u4g9n

We now have the right code format but need to find the right keyword substitution.

Searching on Wikipedia we see a reference to a mountain called “Le Môle” that rises 1,863 meters. Mole is a valid keyword

5eck5moleu4g9n

Separate letters and numbers

daetsnikcalbsiderecnosawtahwdaehymhctarcsdnaffoenoraet

282837284809761767175857589698972857866847579747784788

Seems like we have a phrase written in reverse

tear one off and scratch my head what was once red is black instead

Remember The Riddler in Batman ? His original name was Edward Nygma or E. Nygma. Enigma is a known keyword. Let’s keep that aside for now.

Let’s do the same reverse trick to the numbers and make pairs

88 74 87 74 79 75 74 86 68 75 82 79 89 69 85 75 85 71 76 71 67 90 84 82 73 82 82

Good number distribution for Ascii. Convert decimal to Ascii

XJWJOKJVDKROYEUKUGLGCZTRIRR

Not much, even ROT and Atbash don’t give anything. Now remember that we have the keyword which could serve as a key for Vigenere:

Passphrase: enigma

Message: XJWJOKJVDKROYEUKUGLGCZTRIRR

Result: TWODCKFIVEFOURMEIGHTUTHREEJ

2dck54 m8u3j

Well 54 could mean 6 in Ascii but in this case it’s simple (or not so evident) Niantic math. 5+4=9

2dck9 m8u3j

All that is left to do is to insert the enigma keyword

2dck9enigmam8u3j

This type of cipher was used in a few consecutive posts in the past. The / gives it away as being a keyboard mirror cipher. At one point you’ll also remember some key elements of ciphers like in this case, YOW=TWO.

limibqn/yowltvnwsyiehgyuyowo

sevenpbztwosymbolteightrtwow

7pbz2symbolt8r2w