| Category | Forests |
| Location | Sea of Mourning |
| Region | Aerie of Dragons |
| Map | Iizus Yeldah |
Irengor is a great kelp forest off the southeastern coasts of Feykro Kes. The seaweed is deep and rises up to 400' off the sea floor. Some of the vegetation grows to the surface creating tangles of plant-life which can be so thick that an elf can run across them. These patches can be a problem in the summer for ships sailing through the area. Fortunately for the mariners, the sea elves of Merenwen are always nearby to help those bearing a token of friendship. These tokens are only given to the captains of non-pirate ships and those friendly with the people of Tári Súrion.
In the Demon Spawn War, Irengor was magically enhanced to grow faster and larger. It became like a jungle under the magic of the archangel Tularra. In the vast expanse of this kelp jungle were outposts, encampments, fortifications, and innumerable traps. The forest along with Merenwen and Elbothiach served as the depot for Tularra's armies battling Gorag'theg's demon hordes coming out of the Sôvuk Sea Gate.
Irengor is littered with the ruins of battles fought here in the God Era. Many of these areas are overgrown and forgotten, often serving as the lair of bandits, giant squid, or other undersea beast. The largest ruin is Elbothiach. This place was sacked by the demons and cursed by Gorag'theg. The curse, which not even the archangel Tularra could break, stipulates that any creature dying here rises as undead. The people of Merenwen say that the most terrifying things to come out of the area are giant undead sharks which are even more ravenous when they were living.
Irengor is claimed as territory of the undersea city-state Merenwen.