Certain text string causing internal server error 500?

I’ve run a WordPress blog for years with no problems I couldn’t fix myself, but today I had the strangest thing happen, and I wonder if someone can tell me why.

I was writing up a piece on a new game I’ve been playing, and I do this by typing it up in notepad (at work, they monitor web access time so it’s best I do it ‘offline’), then pasting and posting in WordPress. When I pasted this latest entry, it wouldn’t save a draft or let me publish it, both actions caused internal server errors.

After a lot of time talking to my hosting support, and trying a lot of other things (I could post anything else as a new post and it worked without a problem), I started adding the text a paragraph at a time until I found one which broke it, and then narrowed it down to an individual sentence that seems to be the cause of the problem, this one…

I’ve already changed my main from Guile to Blanka, but I want to be good with Cody and Ibuki.

Every time I add that, WordPress breaks. It makes absolutely no sense. If I add that line as a separate post, it works with no problem. I’ve tried pasting it from notepad to remove all formatting, pasting it directly into the HTML section of the editor in WordPress to avoid any unwanted ‘mce paste’ tags. None of it made any difference.

I’m not expecting a magical fix, and I’ve worked around it for now, I just thought it was strange enough to bring up in case someone else has a similar problem.