Feather of Diatryma Summoning

This feather is a magic item capable of summoning a Diatryma

Upon pronouncing the feather's command word and throwing it into an empty space, it transformed into a diatryma for up to 6 hours, following its summoner's commands and helping its summoner's allies. The summoned bird could also be used as a mount. The bird could be dismissed early if killed or if the summoner pronounced the command word again, while touching it. It then reverted to feather form.

The item can be used once every 7 days