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Sandy Petersen's Cthulhu Mythos for 5e

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Sandy Petersen’s Cthulhu Mythos is the most comprehensive guide to including Lovecraftian elements in your Roleplaying game, written by the author of the groundbreaking Call of Cthulhu role-playing game.

This massive tome contains over 100 monster stat blocks, dozens of which are Cthulhu Mythos monsters that have never been described for Dungeons and Dragons 5e – including new rules for interacting with 25 different Great Old Ones and Outer Gods (they are much more than a simple encounter!).

This is much more than a mere bestiary, however. Inside you will find new rules for Insanity and Dreams; 40 new spells and 30 Rituals – a new magic ruleset; dozens of mythos items and artifacts; dozens of Mythos cults detailed; and four new player races from Lovecraft’s universe – Dreamlands Cats, Mythos Ghouls, Gnorri, and Zoogs – as well as new character options, professions, feats, and race options for them.

If you like Cthulhu, 5th Edition, Monsters, and Madness, you need this book!

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Reviews (1)
Discussions (5)
Customer avatar
February 26, 2022 3:51 pm UTC
If you like Cthulhu [Check!], 5th Edition [Check!], Monsters, and Madness [Check], you will love this book! [:)]
Customer avatar
Stéphanie P December 20, 2020 12:09 pm UTC

Hello, I am sorry if I am using the wrong way for my question. A French translation is published by Edge but only a physical version. There will be a PDF version? If so, do you have a release date? Thank you
Customer avatar
Peter M July 09, 2020 6:05 pm UTC
I am not a huge Lovecraft fan, but I do like a few of the Mythos monsters, and so when this was on Kickstarter, I backed it at the PDF-only level. After seeing the PDF (which was delivered shortly after the kickstarter campaign ended) I upgraded my pledge to get a physical copy.

There's a lot of really good material here. In particular, several of the subclasses (in particular, the trap-focused rogue, ritualist wizard, and mystery warrior fighter) cover specific fictional touchstones that extend far beyond the Cthulhu Mythos itself. The new spells are super interesting and creepy as heck, and the treatment of the monsters and various elder evils of the Mythos are extremely well done.

In addition, the production values are even higher than official WotC books, which is just bizarre to say, but absolutely true. One of the best third-party books put out for 5e. Heartily recommended. Even if you're not a Mythos fan, you'll find plenty to use in here.
Customer avatar
Alex W August 25, 2019 8:27 pm UTC
I got this product from Kickstarter, and therefore can't leave my review on the review half of this page. I however wanted to put my opinions of the product out there. This is the best most comprehensive tool for adding lovecraftian elements to your campaign, and while that alone would be nice Sandy Peterson goes the extra mile with respect to adding said content, regardless if you just want to treat this as a book to add some elements like a xgte-esque book, an extra monster manual, or a full on campaign setting it can work very well in all three capacities. So I will quickly break down my opinions on how this book can be of use to both players and GM's

Extra content for players: There are 22 new subclasses added in, with 5 of them being racially restricted or locked in some capacity. They are all fairly well balanced, but it is important to note that not all of them are combat focused and thus might be a little weaker in some combat situations, but shine more and make up for it in mystery solving...See more
Customer avatar
neil S August 20, 2019 4:16 am UTC
Customer avatar
Anne T June 02, 2020 3:36 pm UTC
Since the publisher is first and foremost a print publisher, and DTRPG simply serves as a secondary, additional source for the PDF, it won't be sold here as PoD. You'd have to buy a hardcopy from Petersen Games directly at
Customer avatar
Alex D June 08, 2021 6:40 pm UTC
It should be noted that due to some technical difficulties, they can't ship to Canada, so Canadian customers have to buy Petersen Games products off Amazon instead.
Customer avatar
February 26, 2022 3:52 pm UTC
Even the PDF?
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File Last Updated:
August 16, 2019
This title was added to our catalog on August 16, 2019.