| Category | Depressions |
| Continent | Karterus |
| Region | Ma'Ohari |
| Owner | Raxcvillibus Dumu-loc |
| Created | 2612 LE |
| Map | Tha'lith |
Toth Coeus is an unnatural canyon in the southern part of Tha'lith. It was created in the 2612 LE, when worshipers of Coeus opened a gateway between Bal-Kriav and Coeus's home world Dol Vahdin. They were able to undertake this great summoning by using an angelic relic called the Irata Phelgas. Without this tome, the type of summoning they were doing would be impossible for any mortal or group of mortals. The worshipers sought the direct intervention of Coeus against the slave masters of Varelay. At the time, Varelay was suffering from the Varelay Upheaval (2608 LE - 16 HE), but even this was not enough of a problem to keep the demon spies of Emperor Aperoq from learning of these insurrectionists. Emperor Aperoq had a special unit hide on a bluff overlooking the summoning. When Coeus came through the gate, they fired a sphere of arcane into the gateway which caused a tremendous explosion. This killed everyone in the area, including the special unit, and brought down the gate. Coeus was half-way through the gate when this happened. He was thrown back to his world and in the wake of gate's explosion was left a deep smoking rift. Aperoq named this new canyon Toth Coeus, meaning "maw or mouth, of Coeus".
Toth Coeus continuously emits reddish hued smoke. Legends say that this unusual color for smoke, is a taint left from Coeus being injured when the gate was brought down on him. The canyon is a jagged area surrounding by miles of broken ground and rubble. It is rich with platinum and gemstones. The difficulty in scaling its unnaturally oily walls and the beasts lurking in the depths have kept the place from being exploited. The perfume Toth Musk is produced from the oil seepage in the canyon's walls. This perfume is widely sought after for its smell and difficulty in procuring.
As a result of its closeness, the builders of the fortress Tas'dvr Mout quarried stone from this canyon. This stone is called Toth Rock. It gives Tas'dvr Mout's foreboding walls and towers an oily and smoky appearance just like the canyon.