24 characters, numbers, capital and lowercase letters can only mean Base64. Decoding as is doesn’t reveal anything good. Let’s try reversing the string

y3r4mJHMDw5JDgLVBJuZmM5Z

Still doesn’t decode right. Let’s change the case of the letters

Y3R4MjhmdW5jdGlvbjUzMm5z

Convert Base64 to text

ctx28function532ns

Make a 4×4 grid

Read going down from the upper right Z

zbm49safety358bq

Using the new Regex Keyword Finder created by agent @SQL input the following string: ^[bur37sfyiep432noc]{7}$

This will give you a list of 7 letter keywords that can be contained in the string. The four results are

Inspire

Oneiric

Rubicon

Success

Out of these, only Rubicon is valid as the others have repeating letters that are not in the code.

Let’s split the string to see how we can make up Rubicon

bur37sfy i ep432noc

Reverse the first and last groups of 8

yfs73rubicon234pe