Spirits: Echoes

"My grandmother left an echo when she fell sick that comforted me until I grew up. I later met the echo of Genaleonder Blue Hands at the battlefield of Tix; she taught me the sword."
— Awanek Graystrider, general

Echoes are the third kind of natural spirits after nature spirits and dead spirits. They come into existence in a moment of utmost importance to someone - the signing of a treaty, finding one's love, the birth of a child, to name a few. It is always very individual.
Most echoes fade over time, but some linger for centuries or millenia, often left by great people, and are popular teachers. The person siring an echo doesn't need to be dead, and echoes aren't dangerous per se.

"A bug fairy's echo - I laughed the first time I heard. But when I met it, the purity of its happiness about having saved the child was truly heartwarming. As was the grace with which it declined the sweets I offered, as if it knew it wasn't corporeal; a knowledge many echos lack."
— Voypa, mage

Not all echoes are aware they're ghosts, and are repetetive, stuck in the moment they came into existence. But they're eager to spread their knowledge; a few of the most powerful even retain the ability to cast spells. Some people have left several echoes, and some parts of the world are filled with them as people leave echoes on any occasion.

Artist's notes
After making the dead spirits very dangerous, I also wanted nice ghosts. It must be interesting to meet oneself as a ghost; echoes do not develop, and by kitaian cosmological philosophy, you aren't the same person at any moment as you were in any other moment, therefore you and the echo are not the same.