Gold Dragon and Spellcasting

[Solinor]

In the MM it describes the spell casting abilities of Gold Dragons as equal to 6th level at very old/ancient age category. I am assuming this is a hold over from OD&D with 6th level being the highest level of spells.

So if amended for editions do you think the gold dragon could cast 9th level spells in AD&D at those age categories?

I have a gold dragon that destroyed a evil human kingdom and the High Kings castle is now his lair. But I see him as immensely more powerful magically than 6th level spells. For example, I see his dreams altering the world around him(effecting weather patterns and such) and his nightmares coming to life. I am of course going to make him as powerful as I want but was just curious if anyone had thoughts about this.

[Lord Cias]

By time the MM came out 9th level spells had been around for a while (introduced in the Greyhawk supplement) and most of the changes made to monsters in Greyhawk were included in the MM. I would say that your standard gold dragon shouldn't have spells higher than 6th level (just as described in the MM) but there's nothing to say that you can't have a special dragon that is more powerful than most.