Spirit's appearance.
This spirit appears as a majestic, healthy young stag of pure white. It's antlers are perfectly symmetrical and at peak growth regardless of the season.
The world the Spirit came from.
Many - The White Stag is a legendary spirit/creature from many cultures and worlds.
Spirit's intentions.
The White Stag or White Hart as it sometimes known acts as a spiritual guide, leading travelers either along the safest route for their journey, or the route that will lead them most directly to their goal.
Spirit's personality and mannerisms.
The Stag does not interact directly with those to whom it appears. It will always appear in the distance and if approached will immediately move away in the direction of the route described above. The Stag is impossible to catch, and can perceive approaching creatures regardless of any method on concealment.
How does it communicate?
It does not communicate in any traditional sense. The Stag serves as a moving guidepost. After a maximum of 8 hours of travel, or when the destination is reached, the Stag will disappear. The Stag never appears to the same person(s) more than once in their lifetime.