I'm taking a close look at the mid-levels of my adventure path, particularly the events of chapters 11 through 15 or so. I sort of just threw chapter numbers on the map, but I want a way to link them together. You'll remember the lower levels are about "experiencing weird stuff" and "figuring out what's going on," so by these mid levels the heroes should be in the "doing something about it" phase.
But doing something can be really simple ("go to location X and do a thing") or very complex ("here is a scavenger hunt/inventory of tasks/list of people/etc.). I want my adventure path to have the latter, where the heroes have to collect several different things for some reason. So I put some thought into that.
I think the "some reason" is to get into the forest where Treerazer is. I *don't* want 10th level characters going there, because they'll get pasted (whether they realize that as players or not being fairly irrelevant). So the 10th level adventure can send the heroes into the Heartwood, only to find that they can't get in; it's magically sealed somehow. They have to figure out how to get in (that's the 11th level adventure) and collect the pieces to do so (that's the 12th through 15th level adventures). In fact, let me plan on linking the 16th level adventure ("find the hidden devil") into this as well, by having the heroes need to get something the lead devil has. So it's like a 4-part scavenger hunt, with some items taking 1 chapter and some taking 2 chapters.
But the 11th level adventure is pretty critical here, since it sets out the action for the next 6 levels or so. Going to get a thing (in this case, a breaching rune to breach the magical border around the forest) should initially seem simple, but get way more complicated. Probably because Treerazer himself knows that the breaching rune is a weakness, and he sends a sub-villain to stop the heroes from getting just what they want to get.
I started framing this out, looking at connections to the prior adventure and the following adventures.
Prior Adventure: The end of the 10th level adventure (which I haven't yet written) ought to involve a knowledgeable quest-giver NPC. I've relied on the scholar Gendal Ink-Hand a lot, but I need someone else. I dropped the name Kessena the night hag back in Chapter 4 as someone that knows what's going on, and I can use her. Chapter 11 should then start with her saying, "look, nobody can get into this forest, but here's what you need to do to get in."
Next Adventures: This needs to point to the forest to the south, because a few things happen here. So maybe this adventure doesn't end with "go get these six things!" and instead ends with "go get these two or three things!" but each is more complicated than they initially appear.
So then I wrote the following adventure!
Chapter 11: The Prismatic Academy (11th level)
At the end of the last adventure, the night hag Kesenna explained to the heroes that the demon lord Treereaver has magically closed the border of the Heartwood to marshal his forces and prepare for an invasion of all the Northfells. Breaking this magical seal requires the breaching rune, a powerful and complex magical rune that requires a ritual to assemble. If the heroes aren’t willing to deal with an evil night hag—despite the fact that her current aims align with theirs—the heroes can get much the same information from the scholar Gendal, who has been researching just this matter since the heroes last spoke with him.
The breaching runewas constructed at the Prismatic Academy, a remote university that was one of the best on the continent for studying extraplanar phenomena. The Prismatic Academy was situated on an island in a lake called Moon’s Tears, and was supported by the small town of Sandby. A mysterious extraplanar incident caused the disappearance of everyone on the island (in the university and Sandby alike) about 20 years ago, and the island has been considered haunted ever since. This is no small reason due to the fact that several dangerous creatures from the Plane of Water now swim in the waters around the island.
Knowing the breaching runecould jeopardize his plans, Treereaver sent one of his best agents to the Prismatic Academy. Tanalissa is a dryad queen who doesn’t like to be away from the Heartwood for long, but she understands the need to find and destroy all information about the rune. She’s brought several vrock minions with her.
Part 1: The Journey to Sandby
There’s really just one way to Sandby: take the well-traveled road to the large city of Kensley, then take the mostly abandoned Lake Road north to the shores of Moon’s Tears and take a boat from one of the small fishing villages. Encounter 1a (Moderate 11)
This adventure begins in an inn called Fandel’s Rest, just east of Kensley. The plague that has been afflicting Kensley has gotten worse, and Fandel—the owner of the inn—is warning people to turn back or take the trails around Kensley instead of going through the city. This conversation is interrupted by four leukodaemons, seeking to spread more disease (although they aren’t the cause of the plague; see Chapter 17). Fandel rewards the heroes with a bag of holding type IIIand lets them know of his cousin Vidar’s old boathouse on the banks of Moon’s Tears at the end of the Lake Road.
Encounter 1b (Moderate 11)
The heroes likely skirt around Kensley, but this puts them in the path of a deadly mantisand agoliath spider. The two titans have been fighting, but each has gained a wary respect for the other. When the heroes show up, they turn on the new, smaller meals.
Encounter 1c
While on the Lake Road headed north, the heroes meet an academic and extraplanar researcher named Zarthu. Zarthu claims to be seeking any lore left behind at the Prismatic Academy. In truth, Zarthu is a veiled master. Its interest in the academy is genuine—it seeks some admittance records in the head librarian’s office—but it intends to betray the heroes whether or not they accept its company.
Part 2: Deadly Waters
The shores and waters of Moon’s Tears are filled with dangers.
Encounter 2a (Moderate 11)
The boat house Fandel indicated is there, although nothing but churned earth and spatters of blood remain of poor Vidar. The large rowboat is still intact, but a purple wormis swimming nearby, hungry for more victims. The boat contains a small chest with a week of rations, a composite shortbow, and a penetrating arrow.
Encounter 2b (Moderate 11)
The open lake contains a large patch of bioluminescent algae. A successful DC 28 Nature check identifies this algae as native to the Plane of Water. On a critical success, the hero realizes it’s similar to a dangerous psychotropic form of algae and knows how to steel their mind against its effects; this hero gains a +4 circumstance bonus to saving throws against sea serpent algae for the rest of the adventure. On a critical failure, the hero inadvertently inhales some of the weakening fumes emitted by the algae and is enfeebled 1 for 1 minute. This area is where two gargantuan snakes made of living water lurk after being pulled from the Plane of Water long ago. Use the statistics of two weak sea serpents, but with immunity bleed, paralyzed, poison, and sleep effects. There are seven strange blue crystals in the algae which can be easily recovered; they are buoyant extraplanar gems worth 300 gp each.
Encounter 2c (Moderate 11)
The Sandby docks have all been badly damaged by sea creature attacks. A tidal masterand sea serpentlurk in this area and attack anyone who comes close. Like the prior encounter’s sea serpents, this one is immune to bleed, paralyzed, poison, and sleep effects—and it doesn’t have the weak adjustment.
Part 3: The Storm in Sandby
The buildings of Sandby are long abandoned, but a few territorial giants occupy the ruins. These giants aren’t Tanalissa’s allies, and, in fact, are fed up with recent intrusions on their island.
Encounter 3a (Moderate 11)
Two evil cloud giants, a husband and wife, live in a large warehouse near the Sandby docks. They know that a recently-arrived fey creature is up to something, as are her vrock minions they’ve seen wheeling about in the skies. They’re therefore quite nervous about even more intruders and fight the heroes; if badly injured, they give up and, with a successful DC 28 Deception, Diplomacy, or Intimidation check, can be convinced to alert the heroes about the numerous vrocks present. The giants keep a storage chest—once a massive shipping crate—with several nice sets of clothing worth 125 gp in total and an eye of apprehension.
Encounter 3b (Moderate 11)
Shortly after the heroes vanquish the cloud giants, a terrible thunderstorm shakes the entire island and persists for several days. This is the work of the storm giant seer Oetekinos, who, like the cloud giants, has finally had enough of the intruders and just finished her control weatherritual to make the thunderstorm. In the thunderstorm, visibility is reduced to only a 100 feet or so, normal fires are extinguished, and sound-based Perception checks and ranged attack rolls have a -1 circumstance penalty. The most immediate threat is that the magical storm brings in two elemental tsunamiswho prowl the town. The low visibility and chaos of the thunderstorm might be a good time for Zarthu to decide she’s been with the heroes long enough, get “lost,” and make her way to the head librarian’s office without them.
Encounter 3c (Moderate 11)
The forest on the other side of the island is the hunting ground of an elite cauthooj. The rainstorm drives it from its forest and it stampedes about the town, giving its warbling cry and attacking anyone it comes across.
Encounter 3d (Moderate 11)
The approach to the Prismatic Academy contains a large glass factory that manufactured precisions lenses and telescopes for the university. It’s been taken over by the evil storm giantOetekinos, where she crafts crystal balls to aid her oracular powers. She intercepts the heroes and imperiously demands they leave Sandby or face their deaths. Heroes who reduce her to fewer than 50 Hit Points and convince her to surrender may gain her as an ally; she may fight alongside them to eliminate the demons and fey from her island home. Her factory includes four artistic but non-magical glass globes worth 200 gp each, a formula for the control weatherritual, and a clear quartz crystal ball, which the heroes can plunder from her if they defeat her, or which she gives to them in thanks if she allies with them.
Part 4: At the Academy
The Prismatic Academy is high on the hill overlooking Sandby. Most of the academy is in ruins, but the squat stone library building is still intact.
Encounter 4a (Moderate 11)
The entrance to the library is guarded by four vrocksatop the building, doing their best to stand guard despite the pounding rain. They join each other in a dance of ruin if possible, and fight to the death.
Encounter 4b (Severe 11)
The central office of the head librarian contains the information the veiled masterZarthu is seeking, but it’s poorly indexed and Zarthu is having trouble locating it all. Zarthu fights the heroes here, intending to eliminate them as troublesome meddlers who might interfere with the veiled master’s plans at a later time. This office also contains a ring of wizardry type IIIand a scroll of summon entity(6th).
Encounter 4c
Some of the reading rooms still contain the empty clothes of students and professors who vanished suddenly during the extraplanar incident. One of these is a cassock of devotionthat attunes itself to the deity of the first divine spellcaster to wear it.
Encounter 4d (Severe 11)
The central archive is where the evil dryad queen Tanalissa and two vrocksare working, finding and destroying every mention of the breaching rune. When the heroes arrive, they work hard to eliminate them quickly and fight to the death. Tanalissa has a traveling bag containing some diseased soil and poisoned seeds from the Heartwood, which she keeps to remind her of her home. This bag also contains a moderate potion of acid resistance. Among the undestroyed materials in the archive is a scroll tube with a scroll of summon elemental(6th). The scroll tube is capped with a gem that is a transparent elemental gem.
Conclusion
When the heroes defeat the foes and recover the remaining information about the breaching rune, they realize Tanalissa has destroyed all versions of it here. However, it can be reproduced with some diligent work; notes indicate that recreating the breaching runerequires special paper procured from a merchant house in the small town of Jortoft and ink from an albino kraken that lurks in the Lake of Eyes. Crafting the rune itself can only be performed by Hansdirk Koladsfar, a former professor who retired to Jortoft before the Prismatic Academy’s accident.