Deep Blue Eyes

There is only one portrait of the very first emperor, the great great great great grandchild of the god creators, Naru and Adonike, that has been preserved to the current age. It is considered to be the only true form of an immortal that was every revealed and captured for the humans to see. It is a mosaic of precious stones, most prominent being the two blue sapphires the monarch has for their eyes. They are rumoured to have a considerable magical power, but many people disagree on what the portrait is actually capable of doing.
The only person who has access to the gallery of rulers is the current emperor and many people believe they themselves are fueling the rumours. Because once you put on the crown you are no longer a human yourself, and who it is to guess what humour do the supernatural favor.
There are also folk tales of people who dared to sneak into the palace grounds to see for themselves and the results are actually amusing to people as well. It seems the first monarch really liked some mischief. And being pranked is really the best case scenario of a punishment you can get, when you sneak somewhere where you are not supposed to be.
The one thing historical records agree on is that the sight of the portrait will smite with lightnings anyone who wouldn't be worthy of becoming the next ruler and yet put on the crown.