Advanced Adventures: The Mouth of the Shadowvein (OSR)

Advanced Adventures: The Mouth of the Shadowvein (OSR)

This installment of the Advanced Adventures-series clocks in at 25 pages, 1 page front/back cover, 1 page editorial/ToC, 1 page SRD, leaving us with 22 pages of content, so let’s take a look!


This review is part of a series of requests undertaken at the request of my patreon supporters, to be undertaken at my convenience.


Okay, so, as always, this module is penned with the OSRIC rules in mind, but conversion to other OSR rulesets is relatively painless. As always, we don’t get read-aloud text herein, and there are a couple of formal differences from the formatting conventions that OSRIC employs, but these, for the most part, apply in a mostly consistent manner. Nominally intended for 6-10 characters of level 3- 5, the adventure is challenging, but mostly in a way that is contingent on how the PCs interact with the environments found and encountered. Attempting to murder-hobo through everything can and will get you killed here. While in the previous module, murder-hoboing PCs could still potentially get away with quite a few things, this stops here – dumb decisions can get PCs killed. Quickly. But similarly, smart PCs may actually be able to best foes far beyond their ability to defeat by force of arms alone. (More on that in the SPOILER-section.) In short: If your PCs is Lawful Stupid, they will die.


There is one more aspect you may need to be aware of: This module represents a taking up of a dangling thread from the very first Advanced Adventures-module, “The Pod-Caverns of the Sinister Shroom” and may be run as a direct sequel to said adventure; knowledge of the previous module is not required, and it is pretty easy to integrate this module into the context of any prolonged underworld campaign or exploration, whether they are mega-dungeon-based or subterranean sagas like AAW Games’ excellent Rise of the Drow campaign. This module also represents the second of two modules that expand the material based on the eponymous Shadowvein, which means that, unless you really don’t want to play the prequel, it’s recommend that you first play “Down the Shadowvein”. The Shadowvein, fyi, is a subterranean river, a black ribbon of water illuminated by purple and green lichen, with tendrils of almost snot-like strands hanging from them – colloquially known as “faerie sputum” to those traveling its length.


From a genre-perspective, we have, much like in its predecessor, a pretty free-form sandbox here – a subterranean hexcrawl, which cleverly uses the subterranean river Shadowvein as a kind of red thread that the PCs may or may not follow. The module does a pretty neat job at depicting the differences regarding the environment and sandbox style play: For one, we not only get different random encounter tables, they differentiate between passage types: You see, the overland hexcrawl map knows primary, secondary and tertiary passages, with different encounters suggested for each.


As a small digression: There are generally two aesthetic design paradigms regarding the underworld, two “genres” if you will: One would be the “civilized” underworld – a realm of vast dwarven fortresses and drow cities, where civilizations both alien and familiar thrive, and then there would be the “weird” underworld, where anything remotely resembling the civilized world vanishes, where strange and chthonian phenomena and creatures roam, where, depending on the setting, one might find entrances to the literal underworld, or even hell. This module, in a smart decision, provides a transition – the Shadowvein, as noted in my review of the predecessor module, very much starts as a trip through “civilized” underworld, while this module represents the PCs leaving these subterranean shores behind in favor of a stranger environments where few upperworlder soles have tread before. However, it does so without a hard cut into the strange, instead using the course of the river to slowly emphasize a transition towards these regions – and VERY FEW modules manage to achieve that; this is the primary reason I copped out and went with two final verdicts regarding my review of its predecessor. In a way, this module represents the payoff and continuation for the exploration of the first Shadowvein adventure.


Considering this, I do have to complain about something: Much to my chagrin and disappointment, the random encounter tables are the exact same as in the previous Shadowvein module (and no, some typo-level glitches haven’t been purged). The encounter tables focus primarily on humanoids, with very few other critters thrown in. This, to me, was somewhat galling, as the module starts transitioning between what one would dub the “civilized” regions of the underworld, and the region that starts to become truly alien and wondrous. As such, a change of pace regarding the tables would have been appreciated. I strongly suggest investing the time and making the random encounter tables more interesting, or rather, different, for this one.


Noja, undal and wyrdwolf stats have been included in this module as well, alongside 3 other creatures – since the exploration of the subterranean realms and the surprise they can elicit is part of the module’s charm, I’ll relegate my discussion of these to the SPOILER-section below.


As before, the player-map of the Shadowvein has been included with its intentional idiosyncrasies still representing one design decision I really enjoyed, and we do get 5 “zoomed-in”, fully mapped encounter areas. I minded the lack of player-friendly maps for them slightly less in most cases than I did for the previous adventure, though one in particular was just BEGGING for a player-friendly map: You see, there is a pretty massive hexcrawl region, with the map spanning two-pages – that one should have been included in a keyless, untagged version at least.


The module contains a couple of new magic items, which include the utilitarian svirfneblin forge stone, a rod that brings the undead back to horrid unlife, an amulet that enhances undead control, a chest that can store a spell to unleash upon intruders, and one item that would represent a SPOILER of sorts – just let it be known that there is a touch of science-fantasy included in the weird herein, with one of the “zoomed-in” adventure locations adhering to that aesthetic.



All right, this is as far as I can go without diving into SPOILERS. Potential players should jump ahead to the conclusion.





Okay, only GMs around? Great! The first complex featured herein is already more interesting than all in the previous module combined:  The lair of Tyrhanidies the lich features his well-concealed subterranean abode, and the mighty spellcaster is using undead as a toll-collecting means. This would per se be unremarkable, were it not for a curious effect  haunting the labyrinthine caverns hiding his belongings and lair: There are strange magical effects here, where gravity doesn’t work properly, and something about them makes those exploring these caves turn stark, raving mad: An innocuous slime causes these visions magically to affect all intelligent creatures (yep, RAW, including the undead!) and the lich has found a way to deal with this, employing the curious property to further shore up his seriously impressive defenses. Now, granted, the PCs may find themselves bypassing this region relatively painless, but we all know how undead spellcasters tend to enjoy press-ganging PCs into doing their bidding…and how PCs are bound to come into conflict with such entities. Cool: Smart and observant PCs either called and escorted to the lich’s abode may realize that there is one object with tremendous sentimental value for the mighty master of the living dead. This, obviously, represents an angle to really annoy the fellow – or to negotiate with a being far beyond the capabilities of the PCs at this level to actually destroy! This is a great area indeed, and its focus on atmosphere, global effects and various means in which you can run it made me really appreciate what was done here.


The second encounter area is pretty much…boring. A grimlock ambush. It exists, but it doesn’t contribute too much to the module’s appeal. After that, we have a svirfneblin outpost that can be construed to be the final waystation of civilization along the Shadowvein’s course, a last chance to rest in a safe environment before the massive, aforementioned hex-crawl sub-region: In a ginromous cavern, the overgrown ruins of a drow city lurk in basically the equivalent of a jungle-choked city of ruins. You see, at one time, the drow that used to reside here managed to capture and harness the godling known as the Pod-God with the help of a demonic patron. It is said entity that ultimately managed to destroy the city, including the artifact employed in imprisoning the entity – this actually did slay the pod-god, but fungi will find a way, and as such, the deity is gestating currently – there will be centuries before the potent deity can reform, but this creates a wondrous environment indeed, one suffused with magic, where stone giants from eastern realms (with an inconsistency in nomenclature), mongrelman and more loom; this region is clearly intended to be expanded, and much to my joy, there are 4 different random encounter tables for each sub-biome of the massive cavern. Oh, one more thing: The gestating pod-god actually wasn’t neutral or evil – it was actually a good entity, and thus, its puffball is guarded by a planetar! With a gate that emits screaming noise and similar, unique environments, this cavern oozes panache and flair galore. This is a great cavern, and would be one of the highlights of the adventure – even remotely capable GMs will have some seriously fun time running and expanding this inspiring environment.


The final encounter are would be unique as well: It depicts the “Green Death Isle” – setting foot upon this island used to see those that dared to do so evaporated, so the hunk of metal there remained unexplored. Well, guess what? That hunk of metal? It’s a actually a flying saucer, and since then, the reactor has run out of fuel, and the defensive disintegration ray? It no longer works. In the aftermath of the reactor’s radiation, a unique people has developed here, namely the terplip, a race of sentient, humanoid mantis-shrimp people! If you’re like me, you raised your hands in the old devil’s horn-gesture and went “Hell yeah!” I mean, come on – mantis-shrimp people? Awesome! We have two different random encounter tables for this region as well, and this becomes even cooler once you learn about the crustacean dragon and the remaining robots – smart PCs may actually be able to save the terplip from their servitude to the draconic creature. Did I mention the laser pistol?



Editing and formatting are good, bordering on very good, on a formal and rules-language level – apart from a few minor inconsistencies and the like, I noticed nothing glaring. Layout adheres to the series’ classic two-column b/w-standard, with a few decent b/w-artworks thrown in. The cartography does its job, and I really enjoyed the inclusion of a player-friendly map for the Shadowvein’s environments. It would have been nice to get player-friendly maps for the trade/social encounter areas at least, though. The pdf comes fully bookmarked for your convenience.


Joseph Browning’s “The Mouth of the Shadowvein” delivers in spades – while two of the zoomed-in encounter areas provide pretty obvious functions and are here to facilitate play (the safe zone) or act as filler (the ambush), the other three regions are amazing. They require smart players and are more deadly than anything the PCs have found so far; there are implied quest-lines that may or may not be taken and used to motivate the players to interact with the factions, and the combination of unique vistas, as a whole, delivers on the promises slowly built up during the previous adventures, while taking up the leitmotif of the original adventure that spawned the notion of exploring the Shadowvein. In short: This is a great little adventure that does a nice job at depicting a region of the underworld that feels like it’s tip-toeing the line between the civilized and weird subterranean realms. It captures the best of early AD&D-aesthetics regarding these realms and molds them into a fun and rewarding expansion, one that ostensibly, like in the previous module, may be taken apart or expanded upon, should you choose to go that route. All in all, this is worth a final verdict of 4.5 stars, rounded up since the lack of a player-friendly map for the sub-region hexcrawl does not warrant rounding down, and this also receives my seal of approval. Come on, the terplip are awesome!


You can get this adventure here on OBS!


You can find the entire Shadowvein-bundle here on OBS!


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Endzeitgeist out.