66 6c 6f 6f 64

Don't worry so much, Sky, this cipher can be understood purely empirically, especially if you paid attention in information literacy classes. Every two pairs of numbers are a code for a character in a hexadecimal system, and these characters are arranged in alphabetical order. Therefore, if the difference between two numbers is one, then the characters they represent are next to each other in the alphabet (we are currently talking about the English alphabet). It is not difficult to guess that the word "flood" is encrypted in the topic title.

66 6c 6f 6f 64

First, compared to the values of the numbers that appear periodically, it is easy to notice that these letters are closer to the beginning of the alphabet. There are two repeating letters in the middle of the word (in English, this is often l or o). The first and last letters are separated by only one letter of the English alphabet. Taking into account Amka's quirks and preferences, one can come to the conclusion described above and verify it by counting the difference between the letters in the alphabet and these hexadecimal numbers. I've done part of the work for you, Sky, the rest is up to you.

However, it won't be easy to deal with base64 code with such empirical ways, yeah