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Rappy
From The re-PSUPedia
Description
Rappies are a small, yellow, bird creature. They're a rare monster and will only appear during a "rare" variation of certain missions. They drop large amounts of Meseta and Rappy Feathers.
There are also special seasonal Rappies. So far we've seen Halloween, Christmas, Valentine and Easter Rappies. These Rappies not only drop Rappy Feathers, but also other seasonal items, such as the Christmas Tree or BT Lovers.
Rappies have appeared throughout the Phantasy Star series since their introduction in III as "Chirpers", which some consider a parallel with the "Chocobo" creatures in the "Final Fantasy" series.