Kalraka Dzeik is a sentient lightning storm with a following of cultists. It has much in common with a natural disaster or a plague; it starts at a single point but spreads like wildfire if given the chance. It is capable of terrible destruction, and will take heroic effort to stop, if it can be stopped at all.
A slight rustle of the wind... and it stands before you. A Unicorn, whiter and more beautiful than you ever imagined it. It has deep wonderful eyes, and you can't help but admire this creature. It came to have a look at you, and now it freely goes. You have not the heart to stop it, and it silently vanishes between the trees.
Note: unless specially needed, this encounter should never happen again.