NM gets angry

But I think it should look clear for you how your pure intentions can be easily misunderstood by the use of that term. You started this thread to get an answer and you already got it, don't keep struggling.

If you had said it at the end of a previous game where you had lost, then I'm not sure why he would take that big of offense to it. I can still see it being disrespectful in that it still literally means "lauhing out loud" though.
I think the guy was just having a bad day and you found the right nerve at the right time lol. I never take in-game chatting seriously online anyways. It's always my assumption that I am playing against an angsty teen with a 20 word vocabulary.

And I said "lol" at one point. That's it
Try "thanks" next time. "handshake" even"gg" though I almost never use that gg on opening blunders.
"lol" will get you blocked a lot. Laughing at yourself all day is fine. Laughing at others...that is simply poor manners.
I find that most players on the edges of my rating zone will abort rather than risk the loss. The NM was a good sport for playing you at all. More grace would have been appropriate.

My apologies, there was a misunderstanding. I would appreciate if you were to remove this post, I left my account open and my brother most likely did something.
Most likely OP's little sister made this thread.

Congratulations kingdamian1
If I was you I would of done more than "lol".
The fact the National Master blocked you is because he was so sad and had grief of his defeat.
It is obvious he is sad at the fact you are his bestest win on your profile page.
Frankly, A National Master has no business playing someone 700 points below them unless they are teaching them something.
Obviously you are not his student so this is appalling.
After the match I would of said " lol Fatality"
Or I would of came up with other very amusing ego boosting comments.
Frankly, beating someone 700 points higher than you qualify as bragging rights exception.
You should of told the National Master a story!
"Long ago but not so long ago I bought a new watch. I loved this watch I bought. However, I did not realize it was damaged and it had trouble telling me the time. For when I asked myself the question what time it is? My watch could never answer;however, after playing against you I have found that answer. What time is it? Its Smack down National Master time. HAHHAHAHAHAHA"
You should of told the National Master a poem!
Roses are Red.
Violets are blue.
I did not lose to you.
I won the match.
You are my best win.
I'm bragging and its probably a sin.

I wouldn't have started a thread in the general forum or called him out...
But you are right that the game would be in the Game Showcase forum faster than the rating could change, lol.
Because as a sign of respect for the game and your opponent, you should win graciously and not laugh at your opponent.
"Well played" goes a lot farther than "lol", even if they blundered into a trap.
Or maybe he didn't like you continuously challenging him?
I'd go for the post-game comment as being the culprit over anything...