Well, the easiest one to answer would be Hori, but unfortunately we can't find any images of it online anymore. It was a poster he got about 20 years ago of a golden dragon locked in battle with a dragon slayer.

As for myself, I don't really have a particular favourite? (I could say my own character sheet, but I'm not so narcissistic)

• Topaz

I like the robot dragons ^_^

• Function

I've certainly seen a lot of dragon artworks that I like~ ^_~

• Mali