If it was open bnet most likely an edit charm. I don’t think you were able to take your closed bnet chars to open bnet. Only single player chars were able to enter open bnet. Edit: I started played at the tail end of 1.08 so i am not sure if it could have been a earlier version

It was on single player.

Are you sure you had a clean install? Just as characters could be edited so could drop tables be.

Never used any mods. Apart from a "no-cd loader" that spared me the trouble of always inserting the cd, no alterations to the game. You think this could impact the drop table? It was also the only time a rare gc ever dropped, didn't happen again.

I’ve played this game for 20 years and never heard of this. You did not find a rare grand charm, sorry.

Ok, sure :-)

Charms cannot be rare AFIAK, only magic and unique.

I know. That's what surprised me as well. I am curious whether there was a known bug or glitch at that time that caused this.

Are you certain that you didn’t grab the item from something else? It’s weird that no one else reported a bug like this. It’s most likely that you grabbed an edited item that someone else dropped.

No, I'm sure it dropped. On single player.

Ni idea then.

Rare charms have never existed in any version of D2, you must've grabbed it from someone on open Bnet or had a mod running.

Yea, I think you're mistaken. Closest thing I remember were hex charms but they were blue and small charms and those were hacked items.