WoWDB

Lorthalium is a world-boss elite that spawns for the mini-holiday event, Hatching of the Hippogryphs.  It is possible to solo if you are the right class, right spec, and a goodly amount of quality gear equipped - though it will take a while for you to kill it.

The hippogryph drops an uncommon-quality conjured item, Spectral Feather, that extends the duration of  Frayfeather Hatchling to five days.