“ When someone befriends an animal, s/he obtains the ability to unite their souls together and take on the form of that animal as well as its abilities. S/he also gain some properties of that animal even when they are no keener t transformed, such as resistence to cold or senses. If s/he really wants to s/he can half transforms taking on characteristics of the animal and their normal form”
“ Marraige custom. The groom must prove his worth to the friends, family, and future wife. The best man is obligated to challenge the groom to a duel and the best man chooses the weapons. (can be anything, toothpicks, cotton balls, anything) If the groom wins then he proves his worth. If he loses then the bride will accept him for his faults and could sometimes gives him a task to accomplish before the wedding.”
“ 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...”