“ Patterns in surnames: There are many ways a surname could have evolved over centuries. One possibility is migration. A Roman name may have traveled to France and hence to England where it was later Anglicized. Case in point - the surname Lawrence went from Laurentius (Roman) to Laurent (French) to Lawrence (English) and then to Lowry (Scottish). There is also natural etymological evolution. For example, a Middle English spelling may have evolved to a modern English spelling (e.g. Stiward to Stewart). Where did your character's Surname come from?”
“ With a huge number of sacrificial victims, another realm long ago secretly bound a Prince of the land spirits, Iorstonn by name, thus ensuring the fertility, and improving the magical defences, of their realm. But binding that Prince to one spot has disrupted the weather and magical patterns (ley lines?) over half the continent. Things have become bad enough that a coalition has been formed to rectify the situation, once divinations have established the cause.
Your party is one of the teams assembled to do the rectification: find the binding object and steal it ('so that we can destroy it here in our realm, of course'...*) or destroy it over there. Presumably the Prince will be grateful to his rescuers and angry at the binders, but with a greater spirit like Iorstonn one can never be sure: such beings are 'tricksy'.
* Of course, the rulers of our realm might want to control Iorstonn for their own ends...”
“ Elven Light Horse - a lithe and small animal well suited to the forest home of the elves. It has semi-cloven hooves, a longer tail, like that common to unicorn illustrations, and always a snow white pelt. Lives inthe forest, able to stand on back legs to crop leaves from the lower branches of trees. Shy and easily frightened, but at peace when around elves.”