A Treatise on the Portals of the Sanctum of Ungalarath.
Having had prior experience with the sanctum of the entity called Ungalarath, I recalled there being several portals within his complex. Fighting my way there through the spent plane, commandeering a ship, and going toe-to-toe with the remnants of his minions proved easier than I remember...perhaps my time in the Society has taught me more than I realized.
The sanctum itself is much as I remembered...I required a very particular key in order to open the door to the room containing the teleportation portals. I tracked down the appropriate species of demon in very little time and procured the required key.
The room's interior fairly hummed with energy. Several of the columns within showed clear dweomers woven into their structures...perhaps the proximity to so many portals resulted in their structural integrity being compromised? This bares further investigation, as we would not want another functioning portal within the Society to result in any structural collapses.
The portals themselves were still humming with energy, still just as active as I left them. A systematic investigation yielded several pieces of information.
1) The shape of all the portals active in the sanctum was in line with the shape of the non-functioning portal in the Arcane Society. This probably means we do not have to alter the geometry of our portal.
2) The banding around the outer edge of these portals appears to be an alloy of iron, mithral, adamantine, and another material my spells were not able to identify. Reference to what was left of the Tome of the Telemancers (spotty as it was) seemed to indicate that the fourth material was probably something native to the plane containing the portal, serving as an anchor so that the portal's structure itself was not drawn through the magical rift in its center. We shall have to investigate suitable materials for the fourth binding material...if memory serves, only the iron band had been installed on our non-functional portal. This means we should begin procuring sources of adamantine and mithral.
3) The portals in the sanctum had intricately carved flourishes sculpted into the front and back of the keystone and footstones of the portals. Further scrutiny revealed these flourishes to be lined with a mixture of ground gemstone dust and another material which varied by portal. Of the portals present, all but one lining seemed to be a mixture of fire opal and ground demon bone...this might be indicative of the destination of the portal. The "correct" portal appeared to have a mixture of ground amethyst (possibly resulting in its purple hue) and another material I was unable to identify with my spellcraft and alchemy lore.
4) As previously mentioned, the structural supports of the room appeared to be reinforced with enchantments designed to buttress them against crumbling. This needs further investigation.
5) The enchantments within the center of the portal ovals appeared to resonate on the harmonic frequency typically associated with transmutation magic on the side of the portal associated with entry, and with conjuration magic on the side of the portal associated with destination. I theorize that the entry side of the portal "tags" the user with a particular harmonic signature, while the destination side of the portal references that tag and enacts a conjuration on the tagged individual. This equates to a fairly simple application of the Shapechange spell (to apply the tag to the subject,) coupled with a near-simultaneous application of an automated summoning spell (a high-grade Summon Monster in the case of intraplanar travel, and a more powerful Gate in the case of travel between planes.) I am familiar with the Summon Monster line of magics, but will have to find someone else more versed than I in the use of Gates, as my knowledge of them is second-hand.
I will file this report in the Arcane Society's library and continue my research using other portal magics in the realm.
Grevaine the Blackbird, recruiter for the Arcane Society
Hank Stone, tinkerer and supporter of the down-trodden
Rembrask Alhavisk, not-so-pleasant mercenary