Santa Claus:
Hahaha... Good!
Rudolph likes to eat "Fresh Herbs" If you feed it this herb continuously, it will grow into a strong Rudolph. You can find the herbs while hunting without much difficulty.
When Rudolph's energy runs low, it will go into your pack, find the herb, and eat it. Remember that he'll want to eat about every 10 minutes.
Also, every time Rudolph eats the herb, it will cast a beneficial spell on you to show you its thanks.
Finally, you have to donate 2019 adena to receive a weak Rudolph. How should I say this... Think of it as your annual donation to help the less fortunate.