Icethorn

It cannot truly be called a "maze", for a maze implies a mere two dimensions. Like the rest of Darkbriar, Icethorn extends in every direction, plants with no roots and no surface, a sprawling labyrinth of needles to impale the weak and unworthy, fed by blood and pain. It is a realm of twisted, thorn-encrusted vines, one wrapped in bitter cold, with the substance of the layer moving from frost-encrusted plant to living ice and back again in a manner that follows no rules or patterns.

Icethorn is cold, and the cold cannot be described as the mere lack of heat. It is heat-stealing, a cold that extinguishes all life, all warmth — the warmth of love, the warmth of compassion, the warmth of humor. The direst reaches of the Shadowfell are a merry carnival compared to Icethorn. To be here is to be drained of all that gives life meaning.

The exact bounds of Icethorn are unknown; it is difficult to say where the maze turns back on itself, and where it blends into the other layers of Darkbriar. At a very rough guess, it fills a distorted sphere some 500 miles across. Some particularly daring or perverse sages have charted a few regions within the plane, areas that seem to distinguish themselves slightly. These are:

• The Spired Tunnels: One area of the plane has formed itself into tubelike passages of nearly pure ice, with great spikes reaching inwards. Howling winds conspire to blow anyone traveling through the center of these passages onto the spikes, but those who can manage to maintain their distance find the Spired Tunnels provide the fastest transit through the heart of the plane.
• The Palace Of The Impaled King: Alalasciane, it is said, was a Ghaele of Winter, one who struck deals with the newly-empowered Zagraleth, offering thousands of souls for sacrifice in exchange for rulership in the Abyss. He was granted his desire, and he sits forever impaled on his throne of frozen thorns, in a vast briar castle filled with those who were his followers in life. A shell of his spirit roams the halls of the palace, while his corporeal form sits in unending agony, so well pinioned that he cannot even twitch.
• The Bitter Rains: Somewhere near the "edge" of Icethorn, the eternal cold is very slightly lessened, and the frost melts into a chill rain, which gathers in pools along thickly interwoven mats of thorns. This water contains the distilled suffering of all those impaled throughout the layer, and as such, it is a potent brew for demons and a powerful alchemical component for those interested in the darkest of arts. It is also a link to the Abyssal river, Dralika, which connects here for but a few dozen feet. All of this adds up to make this region a common gathering point for visitors to this layer, demon and mortal alike, but it also makes the region prime hunting ground. A potent ritual, cast long ago, has created small hidden portals (large enough to hold six medium-sized creatures) which can be revealed and opened if a particular Word is spoken; a second Word disgorges the occupants to some random point in the general area, making it hard for enemies to simply wait for them to emerge. The portal can sustain itself for but a few hours, and each Word can be used but once. Alalasciane would be pleased if the ritual could be forever broken, as he despises uninvited visitors.
• The Sorting Gallery: Souls dispatched from the Shadowfell whose final destination is Icethorn find themselves here — impaled on the spikes and constantly draining blood into the maze, the blood it needs to feed on and grow. The majority are Eladrin whose arrogance had grown to extraordinary levels, to the point where they had no concern for anyone "lesser" than themselves and were filled with malevolent disdain for anyone’s suffering. The majority of those so sentenced will bleed here for eternity, their bodies slowly drifting through the maze as it grows and shifts, but every so often, Alalasciane will send his servants to examine the new "crop" and select one or two, out of hundreds, to dwell with him in his palace and become part of his retinue.

Icethorn is patrolled by Alalasciane’s hunters. These strange creatures, hybrids of fey and demon, roam the maze, accompanied by their "hounds". They will do all they can to keep enemies pinned down, sniping from range, while the hounds close in for the kill. At times, other demons, or special guests of Alalasciane, will join in the sport.

Icethorn Hunter

The Hounds Of Icethorn

The hounds are those Eladrin souls plucked from the gallery who failed to please Alalasciane. Naked and chained, they are forced to run along on all fours, baying and howling. If they speak or otherwise act against their role, their punishment is a return to the hedge, and even this degradation is preferable to that. Their teeth have been removed and replaced with thorns driven into their gums; when they bite, the pain to the victims is usually intense enough to force them to be driven wherever the hounds wish them to go.

Game Rules For Icethorn

Any power with the "Fire" keyword of less than 21st level has its ranged halved.

Saves against ongoing effects with the "Fire" keyword receive a +2 bonus.

Anyone who is the target of a power with the Healing keyword must make a DC 20 Wisdom check; if they fail, they receive only half the hit points they are due.

A DC 25 Endurance check must be made for each hour of travel in Icethorn. Failure causes the loss of a healing surge; failure after there are no more healing surges causes a loss of hit points equal to the character’s level. An Extended Rest in the open restores only half the usual number of surges, unless special precautions are taken. (Rituals, a DC 28 Nature or Religion check, and so on. The DM should be open to reasonable suggestions.) 

(Within one of the portals in the Bitter Rains, none of the above apply.)