Hippogriff in a Jar

This bottle contains a shrunken hippogriff. When opened, the contents reconstitute into a Large effigy of a hippogriff. The hippogriff waits up to 1 round and allows two creatures to mount it, then Flies up to 65 feet and waits 1 more round to give the mounted creatures time to dismount. Creatures who are still mounted on the hippogriff when it dissolves fall Prone in the space where the hippogriff corpse ends its movement.