Mounts can only be obtained during a Winterlight Solstice event.
You need a Percht Skull to exchange for one mount. Dropped by The Percht Queen
There are three variants of the sleigh and three colors each.
Variant 1 : Dark Percht SleighBright Percht Sleigh Cold Percht Sleigh
Variant 2: Dark Percht Sleigh Variant Bright Percht Sleigh VariantCold Percht Sleigh Variant
Variant 3 : Finished Dark Percht Sleigh Finished Bright Percht Sleigh Finished Cold Percht Sleigh
Mounts can be picked up after killing the queen. To get a mount you need to talk to NPC Frosty
NOTE :
Let me add that if you killed the queen once, you can only get one type of sleigh. For example this year you killed the queen you can get all the colors from the first variant if you kill the queen next year you can get variant 2.
Souce: TibiaFandom