Planescape: Fallout/The story so far/Session eight

A white tower in the distance in the center of a salt pan worried our intrepid band of adventurers, but after sending a scouting party ahead at night and discovering no activity, the rest joined them and explored the place, which well and truly seemed to be abandoned. They discovered, roughly in the following order:

• A rich, earthy lichen growing in seven radial spikes away from the tower, which Sejik discovered to be edible on a cursory examination.
• The tower itself was thrust out of the salt pan, and a new 'front door' was made by enlarging a window on what used to be the third floor (now designated '1').
• The overall layout of the tower.
• The former inhabitants seem to be the Doomguard.
• The place seemed to be purposely abandoned--nothing of value was left; the things that were there were the kind of things you'd leave behind.
• A secret room on floor -1 containing a 2 and a half foot diameter circle of a strange green powdery substance, with overtones of insect blood. Hark's portal sense designated it a portal.
• And speaking of Hark's portal sense, he also sensed that the whole area around the tower had overtones of portal-ness, but not a typical one.
• A kitchen with a few old sets of dried goods.
• Many traps on floor 2.
• A secret room on floor 2 where the traps were set, and in which the group discovered a Xaositect journal. (Note: the original language of the book itself is unknown to the characters, and the no doubt earthshaking truths it contains are opaque to them.]
• A scrap of burned paper reading "...tunately, we already had the discs translated before they disappeared, but i..."
• A map, drawn in painstaking detail on the floor of a room on floor 4 (room 15), depicting the surrounding area, which was clearly research done for an epic-level piece of magic.
• An assortment of small amounts of various magical herbs and spices, absconded with by Sejik.
• The fact that some great spell had indeed been cast and was still active in the area, centered on the tower, but with radiating lines in seven directions, further than the lichen went. Indigo could tell that one of the lines went straight towards the portal home.
• The spell was still 'active', and would have to be for perhaps hundreds of years, before finally being triggered in some way.
• The spell depended at its heart on a disruption in the planes.
• The impression of a letter (legible with the charcoal-over-the-page trick) describing to someone's superior that the portal to the Fiery Hall could not be opened, though it had something to do with Fate, but that the other spell was set, and they would be returning to the Plane of Salt.
• An arched window in the very highest 'observation tower' (room 19) with a spike set in the peak of the arch. Hark could tell that this, too, was a portal. The floor was covered with various markings, seemingly centered on the shadow of the window and spike.
• Also, moving the pyramid around, it was hottest the closer it got to that window.
• A copy of a note left in a discarded book, describing something about the Fiery Hall.
• The following inscription over the front 'door' of the tower.