This review has been sponsored by the publisher. Find more DMs Guild Reviews on my website and YouTube channel.

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Designed by: Daniel Kahn, with Dana Floberg (Saving Commodore Krux, Mind Flayer Over Matter), and Charlie Branson (Of Mercanes and Megapedes)

Spelljammer: Adventures in Space released earlier this year. Fans had been clamoring for a proper 5e conversion of the pulpy sci-fi setting for so long, it had become a meme. Yet the three-book-bundle release was met with heavy criticism. Despite the truncated adventure, I was quite positive about Light of Xaryxis — but that doesn’t mean it was perfect!

Designer Dan Kahn returns with another adventure bundle aimed at expanding a published 5e campaign. The three mini-adventures, Saving Commodore Krux, Of Mercanes and Megaphedes, and Mind Flayer Over Matter can all be purchased separately, or together with the Spelljammer Light of Xaryxis Adventure Bundle.

Lucky for you, I’m going to review all three!

Saving Commodore Krux

Designed for 6th level

In Chapter 4 of Light of Xaryxis, the party arrives at the Rock of Bral where they meet up with Commodore Krux, a griff spelljammer captain, and one of the most important NPCs of the campaign.

In the original adventure they simply find Krux hanging out at the local bar. Krux easily joins the crew, though getting his ship back from the scoundrel he’s renting it out to adds a slight complication.

Saving Commodore Krux redesigns the entire chapter, allowing the PCs to witness some of the asteroid city’s seedy underbelly.

In this version, the scoundrel, Fel Adra, works with Krux transporting cargo. Krux discovered contraband on board the ship from a gang of plasmoids called The Amoebros (omg yes), whom Fel has been working with. He dumped the cargo, the gang got pissed, and now Krux has been captured and taken to their base.

After finding the ship and speaking to Fel, the party learns of Krux’s predicament. She leads them to the Secret Grotto, an excellent nine-room dungeon crawl in the caverns beneath the asteroid, depicted as a gorgeous full color battlemap.

The Ameobros hangout includes a guarded entrance (with an easily duped guard), a laboratory with illegal animal mutations, and a fun meeting with the gang leader’s sweet but loyal grandmother.

The final showdown features the gang boss, Ripples, armed with a portal-producing crossbow and two space eels as the party attempts to free the griff.

It’s a fantastic dungeon crawl that integrate perfectly into the wider adventure, though I wish we could’ve seen a bit more of what the Rock of Bral has to offer.

Of Mercanes and Megapedes

Designed for 7th level

The party arrives in Doomspace in Chapter 8, seeking an audience (and an alliance) with the mercane underworld boss, Vocath, in order to raise a coalition against the astral elves who threaten their home planet. 

Before working with the party, Vocath insists they take part in his gladiatorial arena, a classic sci-fi trope and an excuse to trot out some neat monsters.

This wasn’t a chapter that needed any fixing, in my opinion, but here we are!

Of Mercanes and Megapedes can either replace, or supplement the arena battle. Instead of signing them up for the arena right away, Vocath asks the party to retrieve some Megapede eggs from a clandestine supply depot run by thri-kreen.

The thri-kreen are late with their shipment, and the players soon discover why as they make their way inside the abandoned facility.

The dungeon begins with a surprise mini-boss fight against an eye monger hiding inside the secret asteroid supply depot. Once reduced to 40 hit points, Bloatdust surrenders and can provide some limited but helpful information.

After crawling through a maintenance shaft, fending off clockwork horrors, and descending into the cargo bay, the players come face to face with an adult Megapede — and the real boss fight begins!

The Megapede battle features a multi-level arena and lair actions. The players need to snatch the eggs off the rampaging creature’s back before they’re destroyed. It’s a well-designed set-up for classic high stakes D&D hijinks, but I wish the facility were bigger and played up the space horror by a factor of 426.

Of the three adventures in the bundle, Of Mercanes and Megapedes works best as a standalone monster lair.

running mind flayer

Mind Flayer Over Matter

Designed for 8th level

Light of Xaryxis is purposefully filled with awesome cliffhangers at the end of each chapter, and I’m generally a fan of the pulpy design. The cliffhanger at the end of chapter 9 is another awesome moment: just as the party and their armada are reaching the Xaryxian homeworld, they’re accosted by a githyanki riding a red dragon!

Unfortunately it’s a total go-nowhere tease, as revealed in Chapter 10 the rider does little more than say “What’s up fellow space-fantasy kids?” before flying away.

Mind Flayer Over Matter smartly expands this incredibly dumb moment in the campaign with an actual side quest. Or rather, the climax of a side quest!

In exchange for critical information in the upcoming battle, the dragon-rider asks the party to help take down a small conclave of Mind Flayers in a nearby outpost. It’s all a bit random, but so is the damn githyanki showing up!

The gith leads the party to a massive ring gate surrounding a nebula, where a group of Mind Flayers are attempting to a ritual that will open a portal into the Far Realm. If you’re thinking this sounds like the epic climax of another campaign, I’m right there with you!

The storm from the nebula and the ritual causes all kinds of crazy effects (from a d20 table) while the players approach in their ship, while the githyanki takes on a nearby nautiloid.

Our adventurers have to contend with a lack of oxygen and powerful magical effects while attempting to disrupt the ritual. A Cosmic Horror (CR 18) makes its way through at the last moment for an even more epic encounter, as the party must find a way to stabilize or destroy the gateway.

It’s every bit as awesome as it sounds, crammed into only a few pages (with an equally awesome map!). 

Of three adventures, Saving Commodore Krux is my favorite. It integrates perfectly into the campaign and effectively emulates the goofy-awesome tone of the rest of the story. The Amoebros!

After that is Mind Flayer Over Matter. Its quest-line is a bit more awkward and random but the end result is a uniquely epic encounter with multiple objectives and climaxes.

Last and a bit least is Of Mercanes and Megapedes. I didn’t think Vocath needed any extra content, and the asteroid-supply depot is a bit too short and simple, but it’s not at all a bad way to run a Megapede lair.


  • Injects excellent side quests into Light of Xaryxis.
  • Expands meaningful interactions with existing NPCs.
  • Full color gridded and grid-less maps for each location.
  • Troubleshooting notes with combat adjustments.


  • None!

The Verdict: All three Spelljammer adventures expand Light of Xaryxis in fun and meaningful ways — but can also be utilized as satisfying drop-in side quests and lairs for any Spelljammer campaign.

A review copy of “Spelljammer Light of Xaryxis Adventure Bundle” was provided by the publisher. Find more DMs Guild Reviews on my website and YouTube channel.

Support my work by using my affiliate links and pledging via Patreon.