This article contains spoilers for Seasons 2 and 3.
Corellon's Needle is the spelljammer the party discovered in Season 2 not far from the Wizard Research Complex.
The spelljammer contains a stasis chamber, where the party originally discovered Zartok, who had been there in stasis since the events of Escape from Laravella.
It has been upgraded since its original state on ... the floating ship thing, whose name I forget, with ... upgrades I forget the details of.