Legendary Lairs Core Collection (5e)

The Legendary Lairs Core Collection combines the first two Legendary Lairs books with both Extreme Encounters: Weather and Terrain Omnibuses to create a complete modular encounter toolkit for Game Masters who want more cinematic boss fights, dangerous environments, evolving battlefields, and low-prep tactical encounters.

Together, these books transform ordinary encounters into memorable set pieces filled with adaptive enemy tactics, environmental hazards, magical terrain systems, weather effects, multi-stage boss fights, lair actions, recharge actions, traps, and battlefield complications.

Get 4 complete books for the price of 3.

Save $20 compared to purchasing each title separately.

Designed for fast integration into existing campaigns, these plug-and-play systems work equally well for dungeon crawls, wilderness adventures, elemental campaigns, dark fantasy settings, planar expeditions, and high-stakes boss encounters.

Compatible with both the 2014 (5e) and 2024 (5.5e) rules.

Preview of interior pages below.

What You’ll Get

Legendary Lairs: Elemental Lairs (5e)

Plug-and-play elemental boss encounters featuring:

• Adaptive tactics
• Evolving battlefields
• Lair actions and recharge actions
• Traps
• Magical and nonmagical terrain
• Multi-stage boss fights

Legendary Lairs: Unearthly Lairs (5e)

Dark fantasy lairs filled with:

• Cursed terrain
• Psychic horrors
• Plague-ridden battlefields
• Necrotic wastelands
• Shadow magic
• Deadly supernatural encounters

Extreme Encounters: Weather and Terrain Elemental Omnibus (5e)

Dozens of weather effects, environmental hazards, magical terrain systems, monsters, and encounter complications for elemental or adverse weather adventures.

• Air – Magical cloud castle terrain, high elevation areas (including altitude sickness rules), lightning storms, thunderstorms, tornados, windstorms
• Cold – Magical cold terrain, blizzards, frozen lakes/rivers, hailstorms, snowstorms, thundersnow/sleet, winter storms, plus how winter weather impacts travel times
• Earth – Magical Elemental/Fey chaos, caves, chasm/cliffs, earthquakes, forests, hills/mountains, mines (with elevator and deadly gas rules), mud/clay, and quarries
• Fire – Magical fire terrain, burning buildings, fire devils (fire tornados), firestorms, lava flow, lava tubes, volcanic eruptions, and wildfires
• Water – Magical Fog Banks, beaches (rocks or sand), coastal sand dunes/sinkholes, floods (with waterborne disease rules), rain (light or heavy), rapids, river crossings (with or without a ferry), rough sea voyages (ship in storm rules), and waterfalls

The Elemental Omnibus collects these five Extreme Encounters: Weather and Terrain titles:

Extreme Encounters: Weather and Terrain Unearthly Omnibus (5e)

Dozens more weather effects, environmental hazards, magical terrain systems, monsters, and encounter complications for supernatural or adverse weather adventures.

• Acid – Acidic vapors, acid rain, corrosive and slippery slime for Aberrations and Oozes
• Necrotic – Blighted wilderness, cursed ground, unholy ground, necrotic curses and diseases (including a flesh-eating zombie virus)
• Poison – Mutant vermin infestation, poison rain, poison vapors, sewers, swamps, and even fighting in or around a rotting a Huge or Gargantuan monster carcass
• Radiant – Holy ground, solar ground, lunar ground, badlands, deserts, heat waves, sand dunes, and sandstorms (dust storms)
• Spirit – Astral and Ethereal crossroads, ghostly wailing (haunted areas), psychic dreamscape, and soul storm (magical extraplanar weather)

The Unearthly Omnibus collects these five Extreme Encounters: Weather and Terrain titles:

Between all four books, you get:

• Hundreds of modular encounter combinations for dungeon crawls, wilderness adventures, boss fights, and campaign-scale encounter design.

• Systems designed for low-prep Game Masters who want faster setup and more memorable encounters.

Why Game Masters Recommend Legendary Lairs

• Faster prep with plug-and-play encounters.
• More cinematic boss fights and memorable finales.
• Modular systems that fit almost any campaign.
• Practical ideas GMs reuse again and again.
• Designed for long-term campaign support—not disposable filler.

Why Game Masters Recommend Extreme Encounters: Weather & Terrain

• Transform ordinary locations into memorable cinematic set pieces.
• Drop modular weather and terrain systems into almost any campaign with minimal prep.
• Add dynamic environmental hazards, evolving battlefields, and meaningful tactical choices.
• Flexible templates adapt to wilderness journeys, dungeons, cities, boss fights, and exploration.
• Designed for long-term campaign support—not disposable filler.

Awards for Extreme Encounters Omnibuses

SILVER BESTSELLERS

— Awarded by DriveThru RPG (DTRPG)

Average Customer Rating for All 4 Books in Bundle

⭐⭐⭐⭐⭐ (4.9/5 stars)

Top Reviews

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — Marina (DTRPG customer)

"The art for Elemental Lairs is incredible. I also like the layout. The pdf in particular has lots of links that can be used to jump to information easily. [It has] excellent suggestions for adjustments that can be made to games to make lairs and boss fights interesting, epic, and unexpected. Even outside of boss fights, much of it can be used to make more dynamic terrain encounters. Legendary Lairs: Elemental Lairs would be an excellent addition to any Game Master's collection."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — Robert (DTRPG customer)

"MageGate has useful, usable, thematic lairs. The legendary and lair actions help flesh out how and why to use them, adding flavor to whatever level your encounters are set for."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — Neill W. (Amazon UK customer)

"...An absolute masterclass in mechanical depth for 5e boss encounters. The "crunch" is exactly what I look for—each lair provides a wealth of modular tools, from dynamic terrain and hazardous environmental effects to perfectly tuned Lair and Recharge Actions that make every encounter feel like a tactical puzzle rather than just a bag of hit points. What really sets this apart for my style is that these aren't just generic combat arenas; the book actively encourages GMs to weave the boss’s history and motivations directly into the environment, allowing for the kind of narrative cohesion that keeps players fully invested. If you want to elevate your climactic boss fights from simple skirmishes to epic, memorable showdowns, this is an essential addition to your DM toolkit."



⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — Amazon customer

“If you’re looking for inspiration for your boss or their lair, this is, without a doubt, the best work out there.”

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — MageGate customer

"This book has everything a GM needs to run years of cinematically themed encounters and lairs. Best of all, there's zero filler, no lore dumps, just straight up, serious crunch."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — Peter B. (Amazon Netherlands customer)

"This book allows you to go beyond the standard encounters a DnD session usually has and sets you up to create a custom crafted monster lair or themed dungeon where you won't just be fighting the monsters and traps, but the terrain itself. It is a book that helps fill a dungeon/lair with atmosphere that does not just look the part, but adds to the experience. A worthy successor for Magegate's previously released [Extreme Encounters: Weather & Terrain] series. I recommend both as a good little bit of extra seasoning to spice up encounters."

⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — Paul M. (MageGate customer)

"Good plug-and-play book for intermediate to experienced GMs. Lots to chew on. Would have liked more minions and magic items, but the ones it does have are cool and give me a lot of ideas to make my own."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — Kurt P. (MageGate customer)

"What I like most about this book is how easy it is to drop a template into an encounter. I don't have to change anything I wrote, I just add the template on top to instantly make the encounter better. And it's not just for more fun for me (mwahaha!) but more memorable for my players. Since I started using this book, I've never seen them so engaged."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — Jim W. (MageGate customer)

"As a GM, I put a lot of work into my session prep. But since getting Legendary Lairs, I've been able to cut prep time in half. It really is that easy. 5 stars!"

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — Alan D. (MageGate customer)

"This is the kind of book GMs wait their whole life for. It makes me look like a genius. Seriously! There's no way I would have thought of even half the stuff MageGate does."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — Sara G. (MageGate customer)

"Impressive! Covers everything you'd expect and more. Beyond the plentiful lair actions, the mix of magical and nonmagical terrain and traps ensures this book will see heavy use for years to come."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL LAIRS — Oliver E. (MageGate customer)

"I learned more from this book than just about any other book on how to GM. The best part is, it's not just giving advice, it's handing you a 'better GM blueprint' with tons of simple to advanced templates. You can mix-and-match, tweak, and use them over and over. This book is a treasure chest of ideas no GM should live without."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY LAIRS — MageGate customer

"As good as Legendary Lairs: Elemental Lairs, the first volume? I’m even more inspired. Spooky and spectacular! So many creepy evocative names, effects, and creature ideas for a whole host of lair types. There’s so much flavor and crunch you won’t be able to resist adding new story wrinkles to your campaign."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY LAIRS — Robert (DTRPG customer)

“The lair and legendary actions fit the themes so well, and they inspire me to rethink my approaches to locations and boss fights. Together, they add cool abilities, hazards, and threats that bring variety and flavor to your game.”

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY LAIRS — Terry (DTRPG customer)

"The author says ‘You’re not just getting ideas—you’re getting a framework you can rely on every session’ This is exactly right.

So is it repeatable in the sense of repetitive? No. There are so many ideas and such great original flavor in each realm, lairs will never feel like more-of-the-same.

A slow walkthrough building a sample simple lair might enhance the accessibility of the Legendary Lairs series as it might be a lot for a beginner DM."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY LAIRS — Steve R. (MageGate customer)

"This makes my favorite monster and villain locations not only smarter, but a hundred times more fun. Perfect for cursed, haunted, and toxic locations."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY LAIRS — Sean B. (MageGate customeR)

"Get this book if you want to terrify your players! It has so much crazy horror stuff I can't believe it. This is the definitive book for making the game scary again."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY LAIRS — Rob O. (MageGate customer)

"If you love danger and horror—the kind that is sadly missing from most 5e books—Unearthly Lairs delivers. While it's for 5e, it feels very OSR-adjacent. Grognards will love it, but it's not just for them. It's for anyone who wants more out of their 5e game. More thrills, more chills, more everything dark and dangerous."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY LAIRS — Ken K. (MageGate customer)

"I've always struggled to make store-bought adventures feel more like my own, and Legendary Lairs lets me do that. Without stressing, without hours of prep to "fix" them. As soon as I read it, I felt like I leveled up as a GM. That's how good it is. Belongs on your shelf next to The Lazy Dungeon Master and The Monsters Know What They're Doing."

⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY LAIRS — Robin U. (MageGate customer)

"Interesting, meaty book for GMs seeking to bring darker locations like haunted ruins and swamps to life. Older or more experienced GMs will appreciate the many options, but it might be overwhelming for younger/newer GMs. Regardless, it should give them plenty of ideas and inspiration."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY LAIRS — Dirk F. (MageGate customer)

"This is perfect for my dark fantasy-grimdark-gothic horror game. Whether you run Ravenloft or your own sinister setting, this book will give you the tools you need."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY LAIRS — Nick C. (MageGate customer)

"Great book with great art and advice. Easy to read, easy to run at the table. No more boring bad guys or dungeons!"

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY LAIRS — Neill W. (MageGate customer)

"If you find that your 'boss' fights run out of steam fast because of the action economy, then this is the book for you. Its guidelines on giving monsters lair actions and recharge actions keep your party on their toes and, frankly, just make combats more interesting."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL OMNIBUS — Amazon customer

"Too often weather is neglected as an element of TTRPGs, perhaps because it’s too daunting to come up with all the mechanics, but here MageGate has done it for you. Super charge your games with this omnibus, loaded with conditions, effects, and everything else you’ll need to imperil your players in new and exciting ways."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL OMNIBUS — Splinterverse (YouTube Channel)

"Don’t just say ‘You’re walking through the forest.’ There can be so many other ways to bring the space to life! And once you do that [with this Elemental Omnibus] that could lead to some really cool storytelling. I really like this book for the flexibility of the options… really, really fun!"



⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL OMNIBUS — Amazon customer

"This book has a lot of great information for any DM who's running an elemental campaign."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL OMNIBUS — Amazon customer

"In a good D&D campaign, the scenery isn't just to look at. It's to navigate, do battle with, and use to your advantage. Extreme Encounters gives you a huge number of tools to develop fun landscapes."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL OMNIBUS

"Once again, MageGate has produced an invaluable resource for DMs. As well as rules for inserting magical or extreme terrain into your adventures, they also suggest magical items which might go with the area."

— DTRPG customer, review for Extreme Encounters: Weather and Terrain Elemental Omnibus

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ELEMENTAL OMNIBUS — Amazon customer

"Extreme Encounters: Weather & Terrain Elemental Omnibus: This book has a lot of great information for any DM who's running an elemental campaign."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY OMNIBUS — Pat, DTRPG customer

"This is a great resource for any GM running a campaign and wants to add unique terrain features for the party to deal with. I own the entire MageGate collection and highly recommend them."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR UNEARTHLY OMNIBUS — Andrew, DTRPG customer

"Another stellar text from the Mage Gate team. A worthy addition to any DM's collection."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ACID (included in UNEARTHLY OMNIBUS) — Amazon customer

"This book (and the rest of the Extreme Encounters series) gives a whole slew of great options for making combat more interesting. Plus, it's got fun bonuses like a new exhaustion system and explanations of how character abilities interact with the environments."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ACID (included in UNEARTHLY OMNIBUS) — Amazon customer

"The new exhaustion rules seem balanced [and the book has] good ideas on magical terrain."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ACID (included in UNEARTHLY OMNIBUS) — DTRPG customer

"Acid is a very challenging terrain for players. I like the rules for constant damage [in this book] that can be increased or decreased as desired by the GM."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ACID (included in UNEARTHLY OMNIBUS) — DTRPG customer review

"As a DM who seems to attract very chaotic players, I'm always on the hunt for new and exciting ways to surprise them. This book offers a number of interesting (and, naturally, acidic) ways to do just that!"

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR ACID (included in UNEARTHLY OMNIBUS) — DM's Guild customer

"It's full of tasty bits to fill in around the edges of your game."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR AIR (included in ELEMENTAL OMNIBUS) — Amazon customer

"Good information on weather events including tornados. I recommend this book for anyone planning on a sky-based campaign."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR AIR (included in ELEMENTAL OMNIBUS) — Amazon Japan customer

"I was looking for some inspiration for encounters when [players are] flying around, and this provided a variety of different ideas and weather conditions. There were also a number of new and interesting [air and storm-related] magical items, which was very nice. Highly recommended!"

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR AIR (included in ELEMENTAL OMNIBUS) — DTRPG customer

"Good information. Finally some rules for Cloud Castles!"

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR COLD (included in ELEMENTAL OMNIBUS) — Amazon customer

"I am currently writing a winter-themed campaign for my DND 5e group [and] this book is going to help me a lot in my upcoming campaign. Definitely recommend."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR COLD (included in ELEMENTAL OMNIBUS) — DTRPG customer

"Cold weather campaign? This book has you covered. I do recommend this book for any GM running an Arctic Adventure."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR FIRE (included in ELEMENTAL OMNIBUS) — DTRPG customer

"Good rules for burning buildings and handling lava flows."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR EARTH (included in ELEMENTAL OMNIBUS) — DTRPG customer

"Good book with some uncommon rules... fighting in narrow passages and on slopes are a must when actually running a group through a cave crawl."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR EARTH (included in ELEMENTAL OMNIBUS) — Jessalyn S., Amazon customer

"I got a lot of cool adventure ideas from this book! It has great easy rules for running adventures in caves, hills, mountains, forests and mines. This book as well as the others will always find use at my table!!!"

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR NECROTIC (included in UNEARTHLY OMNIBUS) — DTRPG customer

"Interesting rules including unholy ground."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR NECROTIC (included in UNEARTHLY OMNIBUS) — Amazon customer

"The Necrotic book has some great terrains, creatures and magic items. It's a quick read. And these can be easily slid into any campaign. Great ideas and gets you thinking on how you can incorporate them in your game."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR POISON (included in UNEARTHLY OMNIBUS) — DTRPG customer

"Interesting rules, including cramped sewer fighting."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR RADIANT (included in UNEARTHLY OMNIBUS) — Amazon customer

"I like the balanced rules for heat waves. There are rules for Moonlit Ground [for celestials, fey, lycanthropes, etc.] which is something I have never thought of before when running a campaign."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR SPIRIT (included in UNEARTHLY OMNIBUS) — DTRPG customer

"Interesting book with unusual [Astral and Ethereal] rules. I especially liked the Soulstorm rules."

⭐⭐⭐⭐⭐ VERIFIED REVIEW FOR WATER (included in ELEMENTAL OMNIBUS) — DTRPG customer

"It's good to see common sense rules for flooding, including waterborne disease."

Prefer print editions?

Legendary Lairs: Elemental Lairs

• Paperback available on Amazon US
• Hardcover available on Amazon US

Legendary Lairs: Unearthly Lairs

• Paperback available on Amazon US
• Hardcover available on Amazon US

Extreme Encounters: Weather and Terrain Elemental Omnibus

• Paperback available on Amazon US
• Hardcover available on Amazon US

Extreme Encounters: Weather and Terrain Unearthly Omnibus

• Paperback available on Amazon US
• Hardcover available on Amazon US