[RPG] Are there any examples in D&D lore (all editions) of metallic or chromatic dragons switching alignment


In a previous question I asked about a dragon antagonist I am planning. I originally intended this to be a chromatic dragon because I believed they are always evil, but an answer to that question got me thinking.

In the Monster Manual it states that all chromatic dragons are driven by greed and selfishness and are feared by all people.

Likewise, all metallic dragons are good.

However, are there any examples in the lore of either of these being switched? I imagine it would be more likely that a metallic dragon becomes evil than a chromatic dragon becomes good, but are there any outliers at all?

I am willing to accept any examples from any of the editions of D&D or the broader fiction written around the setting.

Best Answer

It really is going to depend on the setting, and what you as DM want to do with it. As far as official settings go, Eberron comes to mind:

From Eberron: Rising From the Last War, page 193, under "Dragons":

The dragons of Eberron aren't restricted in alignment — good red dragons and evil gold dragons are equally common. Most dragons tend toward neutrality. Even those with good alignments often don't consider the impact of their actions on lesser beings; if a Chamber dragon must destroy a human village to foil the plans of a demon, it will do so without hesitation.