Santa Claus is an immortal avatar of good will. All year long he travels around the world, witnessing and participating in acts of kindness and humanity.
Absorbing all of that good spirit on Christmas Eve, he rises into the atmosphere and releases all of that goodwill back into the human race. Santa has been doing this for countless years. Throughout the ages he has appeared in different versions. In 2014 he ended up captured by the Serpent Brotherhood. They wanted to kill him so they could take all of his power at midnight. He tried to persuade Lamia and even made her doubt however it was of no use as he got stabbed with mistletoe by Dulaque .
He later got freed by the librarians who helped him. However Eve gave his hat to Ezekiel which made Santa switch between different incarnations of himself. During the travel he talked with Eve who had problems with Christmas because she was mostly in war zones during Christmas.
They later got on the plane to bring him to safety. However the plane got boarded by Lamia and Dulaque who captured the librarians and prepared to leave with Santa. The librarians tricked Dulaque in putting on Santa his hat which made him order Lamia to leave, release Santa and resulted in Dulaque falling out of the plane. Weakened by the mistletoe Santa gave Eve the power to spread the goodwill of Christmas in which she succeeded.
Positive energy absorption: Santa Claus can channel all of the good energy produced by humanity over the course of a year, absorb it, and release it again, continuing an age-long cycle.
Immortality: Santa Claus cannot die by any conventional means that would kill a human.
Temporary Omnipresence: When spreading the goodwill, Santa Claus can exist in every part of the world for a fraction of a second.
Power Transfer: Santa Claus can temporarily pass his goodwill-spreading powers to a human of his choice.
Shapeshift: Santa Claus's body and personality will change dramatically over the years in other to better blend with humans.
Mistletoe: Santa Claus's powers will be extremely weakened if he touches mistletoe.
Losing his hat: Santa Claus's hat maintains his physical form. Without it, he will start to behave like one of his previous, often pagan, incarnations.