For some reason, the poor crystal horse’s horn ended up getting lost into a portal to some field in merry old England, where an ambitious scientist used it for his latest experiment in reassembling extinct animals, such as the aurochs or the cave lion. To his dismay and the amusement of his audience, it instead built up what appeared to be a black horse with a red horn, whose unusual canine behaviour was found out to be the result of his pet hound mistaking the horn for a chew toy, coating it with its drool and hairs.
The crystal horse was adopted by a neighbour of his who happened to seek for another draught horse to plough his cropfields. To the farmer’s delight and annoyance, Cysgod (as his owner renamed him, after the Cymru word for “Shadow”) always ran around his field to eat the glass in the dumps or dig hole on the ground.
Months of training passed, and Cysgod became rather compliant. That unusual “Friesian unicorn” became the talk of the village: everyone wanted to see if he can play fetch as their kids ride on his back, and if he can do some tricks like their dogs do, only to find that he quickly rushed into the jewellery store to eat its gems. (At least, the jeweller got compensated from the income gained from selling expensive ashtrays made from the horse’s crystalline manure!)