A new Dungeons & Dragons supplement has added new spells and effects inspired by the Cthulhu mythos.

One of the major inspirations for Dungeons & Dragons is the work of H.P. Lovecraft, the creator of the Great Old One Cthulhu and the forefather for an entire genre of fiction that focuses on existential horror, madness, and creatures that exist beyond our understanding. In addition to doomsday cults and strange monsters from other realities, Dungeons & Dragons can also choose to make a pact with Cthulhu or another Great Old One when making a warlock character.

Kobold Press has released a new supplement that adds over 20 new spells, new madness rules, and magic tomes inspired by the Cthulhu Mythos. Written by Chris Lockey, Deep Magic: Mythos Magic contains everything you need to create a warlock that straddles the line between fighting the forces of unknowable evil or succumbing to madness.

At the heart of Mythos Magic are over 20 new "void magic" spells with effects and abilities pulled straight from the Cthulhu mythos. The Curse of Yig temporarily transforms a creature within range into a servant of Yig, one of Lovecraft's ancient serpent gods, while the Hunger of Leng curses creatures with a flesh-eating appetite. Other spells include the Seed of Destruction (a likely reference to the Lovecraft influced Hellboy arc of the same name), which places a quickly growing hydra embryo into an enemy, and the Yellow Sign (a reference that True Detective fans will recognize), which inflicts long-term madness on a creature. These spells should not only delight Cthulhu enthusiasts, they also remain true to the type of strange magic seen within Lovecraft's work.

While these spells are undoubtedly powerful, there's also a dreadful cost to learning them. Mythos Magic also gives rules for "Void Taint," a type of dark influence that comes from learning any of these spells. When a player learns new void magic, they make a saving throw or risk accumulating Void Taint. Whenever a character accumulates too much void taint, they either gain a form of indefinite madness or suffer from some sort of Flesh Warp with effects inspired by some of the strange afflictions seen in the Cthulhu mythos.

Mythos Magic is compatible with Dungeons & Dragons Fifth Edition rules and can be used in conjunction with other Kobold Press products. Kobold is one of the best third-party makers of D&D-related material, and Mythos Magic is a great resource for players who want a true Lovecraftian experience and face the uncertainty that each step deeper into the darkness could be their last.

The PDF version of Mythos Magic is available for $3.99 on Kobold Press's website.