In Generation V, Sawsbuck changes its appearance depending on the current season. However, this change in form does not occur after capture, unless it is present in the player's party at the time of a season change. This applies to Eggs as well.
When the month is January, May, or September, the season is Spring, and it becomes Spring Form.
When the month is February, June, or October, the season is Summer, and it becomes Summer Form.
When the month is March, July, or November, the season is Autumn, and it becomes Autumn Form.
When the month is April, August, or December, the season is Winter, and it becomes Winter Form.
In Generation VI, Sawsbuck is only encountered and caught in its Spring Form. The other forms are available if imported in from Generation V.
Sawsbuck is a deer-like Pokémon that is mainly brown and cream in coloration. In its Spring Form, blossoms with pink petals and yellow insides adorn its horns, with some of the prongs being tipped with cream coloration. Its ears are rhombus-shaped with darker, also rhombus-shaped ear insides. Its eyes have light-orange markings that curve down to sides of its face. Its nose is dark-brown, and its chin, as well as the sides of its face, are cream in coloration. A large scruff of cream fur is present on the base of its neck, with its underbelly, as well as its lower legs, being cream-colored as well. Light-orange stripes rim its underbelly, and its back is decorated with sparse pink speckles. The limbs of Sawsbuck are slender, tipped with hooves and a dewclaw-like pointed feature on the underside of the lower legs, and its tail is low and pointed. Sawsbuck change their appearance with the seasons, in the following ways:
Spring Form: Tuft of cream fur on chest, flowers on growing horns, a little extra fur on limbs, tail pointed down.
Summer Form: No extra fur anywhere except back of head and tail which both curl up, horns fully grown with green leaves, overall a more "alive" appearance, tail pointed up.
Autumn Form: Cream fur back on chest and limbs, horns have red and brown leaves, tail pointed down.
Winter Form: Cream fur on chest and limbs has expanded and is white looking somewhat like a fur coat, horns white and bare, tail pointed down.
Sawsbuck can live almost anywhere in the Unova region as they adapt to the season, but prefer to live away from humans in herds. The herd is led by the Sawsbuck with the most splendid looking horns. The flowers on the horns change according to the seasons.