Mythic Odysseys of Theros

Ok, I finally got my hand on a copy of the book from my friendly local game store.

The Theros sourcebook introduces the second Magic: the Gathering plane as a D&D campaign setting, with its adaptation borrowing ideas from D&D's trip to Ravnica.

While Ravnica is a very odd, very weird setting (being a world that's just one huge city with ten guilds that are all after very different goals) Theros is a somewhat more familiar type of setting. Inspired by (but not entirely based on, exactly) classical Greek mythology, Theros is a world of myths, legends, gods, monsters, and heroes. If Ravnica skews toward a more steampunk or even modern kind of feeling amidst its gothic Central European architecture, Theros is emphatically old-school, looking not only like Ancient Greece, but specifically the "Age of Heroes" as the Greeks understood their own myths - a period that isn't exactly historical, but part of a sort of mythic time that exists beyond any real, literal past.

You won't find Zeus or Hera here, but the Gods of Theros are built along similar archetypes - Heliod, the Sun God, despite being more sunlight and daytime-themed (for MTG players, he's the White-mana God) plays a similar role to Zeus, though his status as head of the pantheon is one that he claims for himself, rather than an irrefutable fact. There are some clear parallels - Nylea is much like Artemis, Athreon is basically Charon, Erebos is essentially Hades, Purphoros is Hephaestus, etc. - but in some ways the roles are flipped around a bit, and we have a world that doesn't just have white people as gods or humans.

Many human-like races from Greek mythology show up as well - in addition to Centaurs and Minotaurs (unchanged, I believe, from their Ravnica incarnations) we also get Tritons (from Volo's, but now with Darkvision, which they should have always had) and Satyrs. We also get the MTG-original (as far as I know) Leonin, which are Lion-people who are tankier than Tabaxi. While these creatures are sort of tied to the color-philosophies that they tend to have in Magic (as typically Red creatures, Minotaurs tend toward chaotic alignments) they also get to participate in the overall civilization of Theros.

It should also be noted that Theros' version of Greek myth is not just based on the ancient myths, but also the more recent, modern re-tellings of that myth. Clash of the Titans, the 1981 movie (and I suppose its 2010 remake) leave a mark here, such as the "Anvilwrought Raptor" (read: clockwork robot owl) and the prevalence of Kraken, which are actually a Norse myth, not a Greek one (not to say the Greeks, and especially the nautical Athenians, didn't have plenty of sea monster myths.)

Feature-wise, there are a few things to really note as novel - beyond new races, subclasses, or monsters (though we will touch on Mythic monsters.)

One of the cleverest aspects of the book is its exploration of Gods. Most players will have a particular god that their character is devoted to - this can range from the benign Karametra, Goddess of the Harvest, to the cruel Mogis, the God of Violence, or any among the 15-member pantheon. Using a score called Piety (which is rather similar to Renown as found in Ravnica) you can earn greater favor with your patron deity, and there are examples for each God as to what you can do to earn that Piety, or what you should avoid if you don't want to lose it. While the more good-aligned gods might be easier to please while playing a heroic character, you might find yourself having to be pretty tricky to make sure you keep Phenax, the God of Lies, happy while also helping save the world.

The benefits of piety range from being able to cast certain spells once a day to eventually gaining a +2 bonus to one of two affiliated ability scores - including a +2 bonus to its maximum, so you can get beyond +5 (a level 20 Barbarian with 50 piety to, say, Iroas, the God of Victory, could have a 26 Constitution).

This expands the importance of the Gods to characters who aren't Paladins or Clerics, which is pretty cool. But if you really don't like the idea of being beholden to Gods, there's even an option for that:

The idea behind Theros characters is that they are heroes of legend and myth. There are even tables to roll on for omens that occur at your birth. And with that, there's also a concept called Supernatural Gifts - each player character starts with one of these gifts, which is a bit like a feat (you can also take a level 1 feat and flavor it as a gift of this sort.) These can range from subtle - like "Heroic Destiny" that, among other things, makes it harder for you to die (because you've got important things to do!) to really crazy, like Anvilwrought, which means that you were literally built out of metal in Purphoros' forge, and as such you have traits that are similar to a Warforged. There are also options that open up different progression paths from the typical ones for piety. Oracles are mediums that can interface with all the gods, and as such gain different benefits for their pantheistic piety. Iconoclasts (which is the default culture for the lion-like Leonin) forsake the gods, believing them to be capricious and vain and not worthy of worship, and as such, rather than piety, Iconoclasts simply get a new bonus at each tier of play.

Finally, the other huge and unique thing that the book introduces is Mythic monsters. There are only three of these options available, though anyone with any experience homebrewing monsters could easily take inspiration. Essentially, these are boss monsters that, when they get reduced to 0 hit points, rather than dying or going unconscious, they go into a harder phase 2, with new legendary actions and a new health bar to deplete. For instance, there is a serpentine gorgon who, upon her "defeat" merely sheds her old skin an emerges faster and deadlier than before.

Given that I'm planning on planes-hopping adventures in my Ravnica campaign, I'll certainly be using a lot of this stuff, but I think you can loot a lot from this book for your own homebrew settings. The Piety mechanic feels like a rather obvious choice, but I also think that Supernatural Gifts feels similar to a concept I'd been working on called "Greater Feats" (the main one I had designed was if you want to play a "blind master" character like Zatoichi or Illidan Stormrage, starting with blindsight and then eventually gaining the ability to use truesight.)

There's stuff I haven't even gotten into here - like how the Underworld is its own whole thing (a character that dies isn't necessarily out of the game) or the various realms of Theros.

While I find Ravnica to be a more original setting, I think you might have an easier time crafting a basic adventure in Theros, given how the stories in this setting are inspired by some of the oldest myths in our culture. It's built around the idea of epic heroes fighting monsters, which D&D is pretty well-set-up to handle.

I do hope that, should they keep making these MTG-based sourcebooks, that we'll eventually get rules on Planeswalking. I could imagine them eventually doing a Dominaria, Innistrad, or Zendikar book, but we'll see. (Actually, I'm really excited to have my players go to Ikoria and fight basically nothing that isn't at least Large in size.)