Best of Greyhawkery and peruse those and many more of my finest work. Now onto the subject of the day: 5 Reasons to Visit Iuz! Well, not the deity himself of course, but more accurately the Land of Iuz proper (not the extended Empire controlled areas). All the entries in this survey are detailed in the indispensable 2E sourcebook Iuz the Evil by Carl Sargent. It's not that I'm biased but there really isn't a better source on this region of the setting. That said, if you do not own this book or PDF I highly advise you go and get it. The maps and content are a DM's dream.
1. Kendragund. The land of Iuz is easy to describe to someone who has never played Greyhawk, but has read or watched The Lord of the Rings; this place is Mordor. It is ruled by an exceedingly evil, omnipotent demigod whose armies are full of orcs and undead. The visuals are immediate and easy to comprehend for any one who plays D&D.
First up is the orcish citadel of Kendragund in the Howling Hills. This is the seat of Iuz's orcish armies in the north, tales saying Iuz began his empire here subjugating the Urzun tribes and with the help of giants, erected the citadel in a day. Today, Kendragund holds a vast garrison of 5000 soldiers, scores of giants and undead warriors with dozens of priests and shamans to drive these forces at Iuz's will. This castle guards the Hills against Iuz's closest enemy, the Wolf Nomads that famously routed the Old One's invading forces at the Battle of Blackwater Bend back in 578 CY (Dragon #65).
Kendragund is ran by Kreshenk, an orog chieftain of giantic strength (F11) whom he delights in torturing prisoners brought up from Iuz's southern wars against Furyondy and the Shield Lands. Those with no political significance are put to fighting against monsters for the entertainment of the humanoids armies. Truly this is a place that heroes would need to tread stealthily in order to rescue someone. That is unless some distraction could cause the formidable garrison to deploy...
2. Dorakaa. The capital city of Iuz's malevolent empire, Dorakaa is called The City of Skulls for good reason and is detailed further in the adventure of the same name. In this module the PCs are tasked to infiltrate and rescue a noble from the most evil place in the world. Dorakaa teems with demons, monsters, orcs, cultists and undead. The sky is literally under a perpetual dark cloud for miles around and the walls have magical defenses unlike any seen in the Flanaess. It doesn't get any worse than this city.
Though Dorakaa is a slum for the most part, it still functions despite the horrors it contains. The city has twisted "Fiend Gardens", Agony Fields where public tortures are put on display, and the Jade Streets where depraved entertainments can be bought. There is artisan and slave quarters where skilled laborers still trade and toil for their masters and the masses of orc soldiery including Iuz's vaunted Legion of Black Death led by the fearsome cambion, General Sindol.
Iuz's top henchmen, the Boneheart, have their own towers and residences here as well, every one just as well guarded and dangerous to visit as the central Palace of Iuz himself. The north wing of this impregnable abode contains the Blackspear Chamber, a permanent gate to the Abyss where Iuz continually draws forth his most fearsome servants. In the middle of the palace behind strong metal doors, is Iuz's throne, a grisly chair constructed from the rib cages of a hundred paladins and clerics of Good. Any PC who ventures to the City of Skulls had best be experienced and equipped with the best magic they can acquire. Attracting too much attention here can easily bring down an overwhelming opposition that no hero can fend off for very long.
3. Road of Skulls. Between the Howing Hills and the capital of Dorakaa is the worst testament to Iuz's reign in the north, the Road of Skulls. Running for 300 miles north-south, this "road" is an astonishing 60 yards wide albeit mostly barren earth. The main trait of his hellish road is at every interval is a pole topped by a skull of various humanoid races. Many of these skulls you see are imbued with magical properties, for example screaming when good-aligned creatures get within a 100 yards or various rays and harmful spells.
Priests and wizards of Iuz, stationed in watch towers every six miles along the Road of Skulls, have control over these magical skulls using wands and staves, so all of this makes openly traveling in the land of Iuz a headache for adventurers. Worse yet, Iuz is now building similar Skull Trails east and west out of Dorakaa. Has there ever been a more foul engineering project in history?
4. Drenghuz. Not all the Howling Hills is controlled by Iuz or the Wolf Nomads. The caves of Drenghuz was once home to orcs (the same kind in Kendragund) but now is one of the most dangerous locations in the all the northern Flanaess. Deep below the earth a shadow dragon of uncertain age resides, though none are sure if it still lives or just slumbers. All the halls and caves surrounding this dragon are filled with hundreds of slow shadows, skulks and worse. Indeed, these denizens from the Plane of Shadow are impossible to control and are much more lethal than normal.
If Iuz's followers won't go here then it must be bad. Surely however, talk of a dragon will attract foolhardy, treasure seeking adventurers who are willing to avoid the keeps, cities and skull roads to take a chance at seeing whether Drenghuz is played out. Most of these characters are probably now part of the lair's population...
5. Icehand Plain. There is many strange and profane sites in the empire, like the Soul Husk Caverns, Devouring Bridge and more, but this last one is rare in that it is only relevant once a year. The Icehand Plain is an innocuous orc camp off the side of the Road of Skulls. On the last day of Sunsebb each year however, Iuz holds a grisly pep rally here.
The leaders of every tribe and army unit along with many Boneheart henchmen and priests attend this mandatory rally. It is said Iuz himself sits upon a replica throne here and a gigantic hand made of black ice appears overhead. This hand points one by one at each of Iuz's subjects, as he divines their loyalty. Those who have traitorous thoughts or waver in their fanatic devotion are blasted into nothingness by a negative-energy ray. Needless to say this intimidates his commanders effectively.
Who cares you say? The significance of Icehand Plain to players and DMs of course is that this is exactly the time and place of the year heroes know Iuz will be outside his palace defenses along with nearly his whole chain of command. It's the perfect opportunity for a hit job, that is if they can brave the icy hand that floats above and a multitude of high level threats all eager to please a paranoid demigod. Your PCs better be close to 20th level for this fight. Good luck!