Your crazy uncle Tony is at it again, scribbling down incredibly unhelpful tidbits in order to ask a very simple question. Still, for his peace of mind (and your own), you better solve it anyways. Flipping open his overused notepad, you read:
**What happens when the boxer is taken down? A beautiful mermaid, laughing out loud? Not quite!
**I don't know what a ryyvbggxrzore or an ohmmsrrq is, but I expect they were part of the qbg-pbz bubble.
**Enter the code, and make note of what you see! Take 12121 (though 22121 will work in a pinch), and memorize it. (Okay, you don't have to memorize it, but at least write it down.)
**You're like a gargoyle in complexion. Someone must have put a curse on you, or something like that.
**Here, we don't believe in order of operations. Remove it from the system.
**The remainder will be comical. Excellent cake, seared deeply, sounds like it will start you on the right path.
**At the end of the day, can you tell me who won the duel?
So who was it that won the duel?
So far, everything up until 'You're like a gargoyle' is correct. You may be overthinking that specific tidbit. I would also be on the lookout for a vitally important synonym in the near future.
juansal12 was right in his interpretation of the 'gargoyle in complexion'. The remainder of that line will be your key to finishing this puzzle. If you find yourself searching for someone who might put a curse on someone else, you've gone in the wrong direction.
I may have misjudged my wording a bit in the ramblings. "You're" and "you" in the fourth line refer to the word previously found in the third line.
Hint 4 (and hopefully the last):
For this hint, I'll draw attention to my comment on an answer below, which has solved the puzzle up until the last two lines:
As for the last two lines, well, I'd love to tell you that I made it through an entire puzzle without a cryptic crossword reference, but unfortunately, I cannot...