A Riddle in the Cipher

Question

You could not believe  
the one that I hate,  
the things that he's done,  
his evil is great.

To utter his name,  
I just couldn't bear;  
but don't worry yourself,  
of his name I don't care  

Tell me the name  
of one autre chC4se,  
the following sequence  
has its nature enclosed:  

I'd like to think that 726L know A76ICD better than anyone,
but a 2D018F2B6J5L goes 3DA5A428ACD73F
from its 2116580KC1 in the 59A15M0J5C5M.
What do 72C6 6CBO55B91F088B
1G7301DABL I reflect 021HAD 8B180G 2E156DAD1LD60C?

A few synonyms could answer that question
but one of those words is the one I need.
It acts a key to the next block of text,
find it and I'm sure you'll succeed.

rybxxqhwhauqqobjcvxtqcvrfezqclzlqowryqepgmyfbzynfgzixfmziopmnyz

Hint 1:

A popular board game about large boats except quadrant I

Hint 2:

French appears in more than just the words

Hint 3:

The first three stanzas are in block-text for a reason. Spacing matters!

Hint 4:

Why do these axes look exactly the same? I can never tell them apart!

Answer 1

As the hints indicate, and along the same lines as MMAdams's answer, we must

take pairs of letters/digits as indicating locations within the block of "verse", Battleship-style.

More precisely,

these are base-36 digits, so A=10 etc.; the first indicates the y-coordinate (0 at bottom, increasing upwards) and the second the x-coordinate (0 at left, increasing rightwards). Spaces are included; blank lines are all spaces.

I remark that

there are a lot of different choices that could have been made here -- axes either way around, starting at 0 or 1, A=10 versus A=0 or A=1, including spaces or not, including punctuation or not. The presence of 0s suggested starting at 0; the fact that second digits in each pair tend to be larger suggested (y,x) instead of (x,y); the very idea of using coordinates suggested that we probably shouldn't include spaces; the C4 (obviously denoting "o") was very informative, and so was the first 2-letter word which seemed like it has to be "je".

This gives us the following:

I'd like to think that je know lui better than anyone, but a camera goes aveugle from its flash in the miroir. What do je ressens quand I reflect sur son horreur?

or in other words

I'd like to think that I know him/her better than anyone, but a camera goes blind from its flash in the mirror. What do I feel when I reflect on his/her horror?

Now, I guess that

the second hint is suggesting that the cipher we need to apply is Vigenere, what with its French name. What key to use? The obvious things are words denoting (1) oneself or (2) negative feelings one might feel on looking at oneself in a mirror. However, I've tried a bunch of such words, both English and French, without success (me, myself, self, moi, moi-meme; shame, honte). ... Aha, got it: the word we need is GUILT

which leads to

the message "letmeknowhowididinmakingmyfirstriddleitwasquitefuntoputtogether"

the answer to which is

that you did fine, thanks.

Answer 2

partial answer

I think this has to do with the game Battleship, which is played on a grid, with numbers on one axis and letters on the other. If the text in the block is our grid, and we letter the rows from A, starting at the bottom, and the 'columns' of characters from 1, starting on the left, C4 is the letter O in "one":
D Tell me the name
C of one autre chC4se,
B the following sequence
A has its nature enclosed:
# 123456789

But the problem I have now is that:

the other text isn't all letter number pairs, sometimes there are multiple letters and sometimes multiple numbers, so I'm not sure how to proceed.

Looking at the words comprised of numbers and letters

There is always an even number of characters in them, so I do think pairs is the right way to look at this. So, 726L is the pairs 72 and 6L. speaking of 726L, I can hazard a good guess that this ciphers to 'we', because it's the only two letter word that grammatically fits with 'know'. It could also be "I" or "you", but those are the wrong number of letters, and "he", "she", names and other nouns would necessitate "knows" following them, not "know". It could possibly be 'tu', but I think that just scans awkwardly.