There was a volcanic eruption of the mountain where Zedar had hidden Torak's body for 500 years following the battle of Vo Mimbre. After Ctuchik seized Errand and the Orb, Zedar went to the mountain and removed Torak, taking him to the crypt at the bottom of Torak's iron tower in Cthol Mishrak. It was theorized that Zedar didn't want his master so close to Rak Cthol, Ctuchik and the Orb, in case Ctuchik could somehow cbc use the Orb to wake Torak and gain favour. The eruption caused panic in the streets of Sthiss Tor when Salmissra was holding Garion later, and Zedar's mountain was still smoldering months later, as the group was escaping across the Wasteland of the Murgos after regaining the Orb. The resulting murkiness assisted their disguises as Murgos in the escape, as it hid some discrepancies (as the group didn't look all that much like a band of Murgos).