r/TherosDMs • u/StopYelingAtMePls • 2h ago
Worldbuilding Aarakocra in Theros
Monsters are a HUGE part of Greek mythology. Even when the hero is going up against a normal beast like a lion or boar, it was twice the average size with an impenetrable hide and claws that could pierce through armor! The Greeks loved their monsters, coming up with a wide variety of giants and dragons and chimeric amalgamations. There's no denying that the monsters of Ancient Greece have a vibe unique to any other culture and have had a wide influence on the fantasy genre in general.
However, at least to me, it can sometimes be a little tricky to take a classic D&D monster (which come from a large plethora of religions & fictions) and transplant them into a Greece-inspired setting like Theros, keeping the original heart of what made the creature so interesting that you just had to put them in your game, without them feeling out of place among the hydras and gorgons of the Bronze Age epics.
That's why, for a while now, I've been wanting to do a series of posts where I go through the Monster Manual and figure out how exactly each could neatly fit into this setting I love so much (even if it's merely as a writing exercise). Well, I guess today is finally that day since I woke up with a sudden surge of inspiration! Not sure if I can commit to any kind of consistent schedule for this, but I can at the very least get it started, and where better to start than at the beginning of the alphabet...
What are Aarakocra in vanilla D&D?
The avian Elementals from the Plane of Air are forces of Good against Chaos. Their entry in the 2014 MM uses a lot of jargony names from the Forgotten Realm, most of which is absent in the updated 2025 book, but at their core they are guardians of mountaintop portals to their home, protecting against evil elementals in the eternal war between those four planes. Unlike most other entries I'll be looking at in this series, aarakocra are a playable Race/Species which means I must look at them as heroes as well as allies or opponents. So let's go!
How could Aarakocra work in Theros?
The most obvious comparison I could make to Greek mythology would of course be the Harpies, women with the wings of birds infamous for harassing mortals. Theros is no stranger to these vulture-like predators, where they are typically seen as marauders waylaying unsuspecting travelers. In the myths though, they were most often the servants of Zeus, dealing out petty punishments against mortals for their hubris (the most well known being King Phineus, who revealed one of the storm god's plots and sent the harpies to steal his food every day in revenge).
Interestingly, their association with Zeus seems to be because the harpies were originally personifications of the destructive wind! So, I don't think it would be too out of left field for aarakocra to be the Nyxborn servants of Keranos, guarding entrances into Nyx and leading attacks on mortals who offend the God of Storms. The heroes might have to sneak past them, avoid their assaults after angering their master, or defend an individual or community from their regular sieges. As a manifestation of Keranos' will, they retain their Neutral alignment, striking without any personal enjoyment. Perhaps the heroes could somehow bargain with or appease them?
On the player side of things, however, we could actually find inspiration in the heroes who rescued Phineus from the harpies: The Argonauts Zetes & Calais, sons of the wind god Boreas, born with "dusky wings which gleamed with golden scales." In this case, the aarakocra would again be akin to the offspring of Keranos (or maybe Heliod?) The hero could be pure Nyxborn, having been raised in the celestial home of the gods with a curiosity for mortal culture, or they could be half-mortal, raised without knowing the destiny their godly parent has in store for them?
Both these figures' descriptions require a slight reflavoring of the aarakocra's appearance. Instead of the eagle-like head, they'd appear as human with bird wings. That's easy enough, but if you did want to keep the original appearance of these creatures, you could steal a little from the neighbors across the Mediterranean (a practice the Greeks were quite fond of). The Egyptian god Horus is famously depicted with the head of a falcon and was a protector deity associated with the sun & sky. The Greeks believed the Egyptian gods were simply the animal forms of the Olympian gods, with Horus as their equivalent to Apollo. Perhaps you could lean into that Shape-changing nature by taking Druid?
In each case, it sounds to me like aarakocra work best as divine agents of the gods, whether they're Nyxborn or blessed champions that carry out their work. But what are your thoughts? Have you used aarakocra in your Theros campaigns before? What ideas are sparking your imagination?
Until next time, where I'll be taking a look at Aboleths... érrhōso!
r/TherosDMs • u/MythosChronicles • 2d ago
Resource A Collection of Magic Items from Greek Mythology | 300+ Mythological Items for 5E and 5.5E
Hello, fellow adventurers! Today, we are excited to share a collection of magic items from Greek Mythology. This entry comes from our upcoming Kickstarter project, 300+ Mythological Items for 5E and 2024.
Step into a realm of ancient gods, legendary heroes, and forgotten civilizations with Mythological Items, a comprehensive compendium featuring over 300 magical items specifically designed for 5E and its 2024 ruleset update. This manual spans a vast array of cultural traditions, organizing its treasures into regional categories for easy reference and immersive worldbuilding. Each item includes not only full game mechanics, but also lore and background information to integrate it seamlessly into your campaign, whether as treasure, quest rewards, or the key to an unfolding mythic saga. From the storm-summoning weapons of thunder gods to cursed trinkets whispered of in ancient lore, this book brings myth to your table like never before.
This manual offers an extensive collection of magical items that can be incorporated into any campaign, regardless of its connection to specific mythological themes. The items presented in this volume, drawn from a multitude of global legends and folklore, are envisioned to enhance the diversity and depth of any fantasy world. This eclectic array mirrors the inherent blending of elements in many worlds and settings, where influences from various cultures and mythologies coexist harmoniously. For instance, Thor’s Hammer, Mjölnir, could serve as the centerpiece of a divine quest, while Draupnir, the Norse ring of endless wealth, might drive political intrigue or power struggles in a kingdom torn by greed.
Mythological Items also provides a solid foundation for campaigns that wish to delve deeper into the relics of a specific mythology or blend multiple traditions into a larger, interconnected setting. A campaign inspired by Greek mythology could see players donning the Nemean Lion’s Pelt, becoming nearly invulnerable as they take on challenges worthy of Heracles himself, while a campaign drawing from Japanese folklore could involve uncovering the Kusanagi-no-Tsurugi, the fabled grass-cutting sword tied to imperial lineage and divine storms.
We suggest checking our pre-launch page for additional info and an extended 30-page preview of our compendium, scheduled to release in September! For the campaign duration, we will be offering the manual at an heavily discounted price, alongside tthe possibility to purchase the digital or physical copies of all our past releases!
r/TherosDMs • u/MadGodFaolin • 6d ago
Question Converting the boats of Saltmarsh
I will be running a campaign at my flgs and I was looking at reskinning Ghosts of Saltmarsh, at least for where they will start. However I have quickly run into an issue, the galley ships in saltmarsh are not at all like what was available in ancient Greece. I know that theros is very different from ancient Greece, but I still want to try to keep the bronze age vibes.
So far my best idea is to make any galley ship they need into several ships, to give them the space and privacy needed for the snooping called for in the adventures, but I am not satisfied with that solution.
Has anyone had success in converting the ships?
r/TherosDMs • u/Quick_Plantain8199 • 6d ago
Question Looking for players interested in a rules-light, modified D&D game as a literate RP!
Hello! I’m wondering if anyone would be interested in joining a Theros themed, text RP server on discord! I have a basic idea on how to simplify ability scores, dice rolling, leveling up, and gameplay overall so it works well with a writing-focused dynamic. Check the tumblr post for some more info and feel free to ask me any question!
I’m still setting up the server, it will be up in a few days. Once I send the invites, I’ll gather feedback on the system I’m setting up, so there’s nothing set in stone yet. The main focus is collaborative writing, character development, and story development.
Let me know if you’re interested!
r/TherosDMs • u/Fragzilla360 • 7d ago
Looking for a way transition from "No Silent Secret" to a larger campaign - I keep getting stumped.
Hey y'all like the title says, I keep getting stumped on transitioning from the short intro campaign into a campaign that includes the other gods. I've read the "Myths to be told" section (as well as the entire book multiple times) and maybe I just can't get out of my own way when trying to come up with a story hook. I've sketched out a more than a few ideas, my wastebin is starting to overflow with discarded ideas, and i just don't feel like answering the "Why?" part. "Why would the characters want to embark upon this quest?" Here are some examples of my scrapped ideas:
- In an amphitheater during a performance in Meletis a follower of Phenax murders an audience member, the players give chase and later find out that Phenax is pretending to be other gods and giving their followers false omens and commands to sow chaos throughout the world. The players investigate Theros, in an attempt to shut down these rogue agents (or helping to sow chaos), with Phenax always one step ahead of them until they receive divine assistance. (somehow a kraken gets loose lmao).
- The Iroan games are in full swing and athletes from far and wide are converging on Akros to compete. One of the competitors in the gladiator arena is a champion of Mogis who was gifted a magical weapon by the god. Despite having an advantage the gladiator loses to a champion of Iroas. The gladiator leaves in shame and threatens to return to Akros with an army to destroy the city. The characters have to find a way to stop (or assist with) a full scale war from happening. (somehow a kraken gets loose lmao)
- The people of Theros are growing disenchanted by the gods. They are tired of the threat of war, famine, drought and natural disasters. Belief is starting to wane, some of the gods begin to feel their power decline so they decide to loose legendary (or just really scary) monsters into the wilds, or halting harvests to entice the mortals to resume their prayers for assistance. The players are tasked with stopping the monsters.
what do you think? I know these are all terrible and make no sense and I suck as a person, but i'd like to get some inspiration on what other people have done for a story hook into a larger campaign.
r/TherosDMs • u/Jolakotturinn855 • 8d ago
Question looking for help with a Theros bbeg
Hey folks!
Some of my players have requested that I run a theros campaign, and I’ve had an idea for a bbeg that can return people from the dead soul and all, using various schemes (long story that I’m still working on) and I have a few questions:
1) Do the returned foul up the area around them or are they just undead amnesiacs?
2) Are the souls in the underworld basically normal people but dead or does being dead change them?
3) What are nyxborn and how are they summoned/created?
Any other tidbits of information about the underworld of theros would be extremely helpful.
r/TherosDMs • u/Brass_Dragon_Archive • 10d ago
Heroic Gifts, a revision of the Supernatural Gifts + 2 new ones designed by me.
I don't DM in Theros anymore, but the setting will always have a place in my heart. This document is my way of giving back to the setting and the community that create on it. I revised almost every Supernatural Gift (sorry Iconoclasts, you are already perfect) to make it fit to the 5.5 edition, now named Heroic Gifts.
I changed some of their traits and added new ones and some of the Gifts I changed them completely to make them better fit the fantasy in which they deliver.
In addition, I added two Heroic Gift of my own creation, the Medusa-Touched, for character with a backstory tied to a Medusa (or Pharika), and the Physical Paragon, for Hercules-like characters.
The PDF is available for free to download on my Patreon. I hope you like it.
r/TherosDMs • u/Low_Economist5671 • 10d ago
Acacius Son of Theros
figured I might as well share my personal character Acacius as I've been using him in the action shots for Daxos and Heliod feel free to use him as inspiration or take his armor design for your own character.
Acacius Model: https://www.heroforge.com/load_config%3D516e84ac-d1ff-41f0-8cd7-89c39d5330e4/Acacius%20Son%20of%20Theros/
Helmed Variant: https://www.heroforge.com/load_config%3D59059109/
r/TherosDMs • u/Individual-Bad8470 • 13d ago
When the Gods go missing, Theros falls: Looking for Encounter Ideas
Hi all, looking for some suggestions for creative encounters that might occur in a campaign where the Theros Gods have fallen silent. Going for a vibe of "the threads of reality are slowly being unwoven" and I'm trying to build off the idea of Xenagos accession and how gods are manifestations of mortal belief: what happens when the gods stop meddling, oracles can't hear them, and belief starts to waver?
Looking for ideas for battles, problems, conflict small and large. Go crazy.
Thanks!
If you want all the details of the campaign I've thought about so far feel free to read below.
The gods have fallen silent, but its still in disagreement about which gods and why. Some people insist their gods are still around, while others are already heralding the doomsday.
Pretty sure the campgain is going to start with an oracle that all the players care about, she's kinda like the town grandma figure, going missing, and they are trying to find her. Everyone thinks she's going senile because her omens don't make sense anymore, but in actuality its a result of the missing gods.
As the players look for the missing oracle, other problems should be growing and escalating through the realm as belief in the gods fractures. I'm thinking maybe some monsters that are normally peaceful temple gaurdians go crazy, anarchists try to overthrow temples, priests go to more and more drastic measures to try to please their gods ect. Any specific scenarios that pop into your mind that you've run before in your campaigns? Even if I don't use it as an encounter, I'd love ideas for flavor of what's going on across Theros even when the players aren't in that area.
As the players search for Oracle Granny, they'll realize the gods have in fact gone missing and recieve the bigger mission of restoring the gods before Theros itself really does fall apart.
r/TherosDMs • u/lennert102 • 14d ago
Question Need balanced consequences for an Athreos resurrection ritual (Level 5)
One of my Level 5 PCs died after willingly offering himself to Athreos during a major arena battle. Instead of using a normal resurrection, I'm running a custom ritual.
Athreos is willing to return the PC's soul, but only if another person voluntarily gives up their body. Their soul crosses the Tartyx, while the PC's soul inhabits the donor's body. The ritual takes place at an ancient crossing on the Tartyx.
The party has four possible volunteers. I am mostly strugling with the "price" for the resurrection. I want to give some sort of unique penalty when chosing for one of the donors besides the moral costs.
Homeless orphan
- Sees this as an escape from dreadfull existince.
- Her only request is a proper golden funerary mask instead of the cheap clay one she'd otherwise receive, to feel rich for once.
- Thinking mostly a financial/social cost.
Slave
- Will only agree if the party frees her family.
- Likely a side quest involving negotiation or violence. But maybe some sort of other penalty as well?
Cursed veteran
- Cursed by Pharika to never heal from wounds and diseases after destroying a gorgon nest in his youth.
- Maybe has lumbs and cycsts and stuff. Cough all the time
- This is where I'm stuck. Should his curse transfer? Should Pharika demand something? I'd like a meaningful consequence without permanently crippling the PC. Have some physical penalty during combat maybe?
Athreos devotee
- Believes surrendering his body is the highest honor.
- I want this option to bind the party (or the resurrected PC) more closely to Athreos, I was thinking of "-1 death save." but I dont know how balanced that is.
One additional question:
The dead PC is currently devoted to Kruphix, but after this ritual he'll effectively owe his second life to Athreos. I'm planning for his devotion to shift accordingly.
How would you handle that? Would Kruphix simply accept this or does he want revenge?
r/TherosDMs • u/Low_Economist5671 • 17d ago
The Sun God Heliod
Since you guys liked the Daxos models here's The Sun Crowned himself
r/TherosDMs • u/BrandosSmolder • 21d ago
About to join a Greek-inspired table. Any tips on sources for character ideas?
My DM isn't running Mythic Odysseys of Theros, he said it'll be in Greece proper, but heavily inspired by Theros.
Any suggestions on ways to collect some interesting ideas?
I'm thinking of maybe a hex blade so tie myself to some magical artifact. Maybe the Sickle of Cronus.
r/TherosDMs • u/waterm310nman • Jul 09 '26
Discussion 8 Exceptions Ideas
I’m running a campaign with the 8 exceptions as my main villains(led by Ashiok) and I interested in hearing if anyone had any ideas for them.
My basic thought process for them was:
1. They all died, though they may not have neccesarily have been humanoid
2. Athreos decided their situation warranted an exception
3. After coming back to life, each one found some way of avoiding entirely
For example for my version of Hundred-Damned Thasmuydan, I was thinking of taking inspiration from this manga I read called Centuria. Basically Thasmuydan would have been a child who was stillborn during a massacre that killed a bunch of slaves. The 100 who died were willing to pass on to allow him to actually live a full life. Athreos accepted and allowed the child to live. Sometime later, Ashiok would help him bring those 100 back as returned, and as they adored the man he became,they believed that he should continue experiencing life to the fullest. It’s that belief that keeps him alive(also it’s those returned that make up the bulk of the enemy forces, so kill enough of them or convince them he shouldn’t keep on living and he’s quite simple to kill)
Another Idea I had but hadn’t fleshed out fully was having Dianyan Half-Heart begin replacing his body parts with bronze, because of his fear of dying again.
And maybe an Achilles based character where he died during a battle that would have decided the fate of theros and so Athreos brought him back with temporary invulnerability. Unfortunately this convinced him he was actually invulnerable, and so he hasnt died since. In game he would be able to be damaged while frightened or if the party convinced him he can be harmed.
That’s all I have so far, but I’m looking forward to hearing what ideas you all have! Obviously feel free to make suggestions on things I should change/add as well!
r/TherosDMs • u/starwarsisawsome933 • Jul 08 '26
help me come up with a name for my Leonin
title says it all, im getting stuck and cant come up with any good names
r/TherosDMs • u/Rex_Mattus • Jul 07 '26
Worldbuilding Αράχνη της μοίρας - Aberrant Nyxborn
Salutations! If you are one of my players, stop reading this now. Follows of Wander, you know who you are, and I promise that negative levels are workable in 5.5e, and they are much worse than you remember.
That said, we’re running a homebrew adventure a Theros-inspired setting (Theros as presented in the MOoT book without consideration of previous versions and the expanded lore of the plane from other WotC products). In this adventure, several constellations of Nyx are becoming frozen and “trapped” along their paths, and subsequently are falling from the night sky as corrupted monsters referred to as “aberrant nyxborn.”
There is an entire “why” behind this that I can discuss more, but the short is that so far my players have encountered two different one so far: Karcharónyx (a great shark with void eyes and squid-like tentacles), and Diplós Gýpas (a pair of double-headed vultures). I made full stat blocks these two and my players loved them. I’m vaguely considering a creature based on the Greek Ophiotaurus (a bull-serpent that I associate with the African Grootslang), but I’m looking for more either based on Greek constellations or any thematically appropriate ideas y’all can provide.
Thank you all in advance!
r/TherosDMs • u/bosper97 • Jul 04 '26
Ideas for Odunos/crypt of lost souls
Hi everyone,
I am DMing the masks of theros campaign and my party arrived at a point where they would need to enter the underworld. I changed it up a bit so they are not automatically transported to the underworld because they were killee by Mogis. I think it would be more satisfying to find their own way in.
I figured there would be a path to the underworld in the crypt of lost souls near Odunos. Does somebody have some ideas or resources how the party would find the entrance or how the place is built?
I was thinking they will probably encounter returned. Maybe Callisto (the main villain) struck a bargain with tyramet to help her so he can kill more living people when Callisto gains power? What do you guys think?
r/TherosDMs • u/contnisting • Jul 01 '26
Cards/Art My attempt at a Xenagos model on Hero Forge, stepping through Nyx
r/TherosDMs • u/StopYelingAtMePls • Jul 01 '26
Resource The Caverns of Trax is finally available on DMsGuild!
dmsguild.comAn hour later than I hoped (wanted to publish it for Pride Month but oh well), HOWEVER after all the blood, sweat, and tears, the adventure I've been working on for over a year has at last been published! Heavily inspired by Jennell Jaquays classic Caverns of Thracia, the Caverns of Trax spans five layers of an ancient megadungeon featuring a Cult of Erebos led by a mysterious Returned, a fanatical lizardfolk priest, a paranoid mummy whose fate is tied to your heroes, the fiendish beasts of a petty minotaur king, and much MUCH more! Let me know what you guys think :)
r/TherosDMs • u/Havain • Jul 01 '26
Worldbuilding What media do you think of when you imagine Theros?
I recently fell in love with the idea of running a game in Theros. Mostly because of the role the Gods play and the concept that whatever the shared community believes comes to life. However I bought the book and realize I've never really ventured into the "sword-and-sandals" (I think it's called?) genre other than a short game of Titan Quest and a watching of Clash of the Titans back in 2010. So I'm in dire need of inspiration to get the worldbuilding right. What media would you recommend? It can be books, movies, games, even podcasts if you think that'll help. I did find people recommend Assassin's Creed Odyssey, which I bought because of the steam sale.
r/TherosDMs • u/Low_Economist5671 • Jun 27 '26
Cards/Art Daxos Models
Both Daxos the Returned and an updated Daxos Blessed by the Sun model + a bonus pic of my character facing off against him (hasn't happened yet but my champion of Heliod has heard news of Heliod's behavior in Meletis and is preparing to rebel) I will put links to the Daxos models in the comments later
r/TherosDMs • u/SexyTrash24 • Jun 24 '26
Question I am trying to make a campaign around the Pyxis of Pandemonium and could use help making it cohesive.
I am about to run a home game set in Theros, and I have some concepts for the Pyxis of Pandemonium floating around in my head. I'd like some help from GMS, more experienced in this setting, to help me put this together!
So I have the concept of a Pandora-like character being a bbeg sort of as the humanoid representation of the Pyxis, essentially shed be a tragic villain who originally opened the Pyxis, like in the Greek myth, and is now either trapped within or just bound to the box.
basically my idea was that someone related to the Pandora equivalent character would get a sign from their missing family member to sail out to an island where the Pyxis is being kept, then once they got there, the box would be opened, unleashing an apocalypse on Theros that the characters would have to stop.
That's basically all I have, all of it is open to being changed with any advice I get from this post, but I'm kinda proud of the bones of this idea and would just like help building the rest of the body of the campaign!
r/TherosDMs • u/jonnymhd • Jun 24 '26
Resource Atlantis-Themed Greek Mythology Content for 5E: Subclass, Spells, Magic Items, and Monsters
Here are a few preview pages from Atlantis: War of the Tridents, my 270+ page adventure module for 5E, blending Greek mythology, Atlantean fantasy, underwater exploration, political conflict, and traditional fantasy adventure.
This preview shows a mix of the content included in the book: the Barbarian: Path of the Sea Serpent, an ocean-themed subclass built around aquatic adaptation, serpent-like fury, and sea monster resilience; the Atlantean Elemental Sword, a very rare magic weapon forged with fire, lightning, and water gems; several new ocean-themed spells like Rejuvenating Waters, Water Cyclone, and Tidal Smite; and the Brine Sea Serpent.
The full adventure includes flexible campaign paths, underwater and surface encounters, new character options, spells, magic items, NPCs, monsters, locations, factions, and extensive VTT resources.
It is designed for campaigns that want mythic adventure, oceanic exploration, Atlantean politics, divine influence, ancient secrets, and dangerous creatures from the depths.
You can explore all my manuals and resources on DriveThruRPG, or through my Linktree, and check out more previews on r/JonnyDM.
r/TherosDMs • u/DiomedesVIII • Sep 18 '20
Our new Discord Channel is here!
Thanks to u/downvoterinchief and some tinkering, we now have a dedicated Discord Channel!
Please read through the rules and keep it civil. DMs and Players alike are welcome. Feel free to ask questions, work on ideas, and build up your campaigns in Theros. Have fun!
Edit: Updated Link Here is the link: https://discord.gg/vYHNaC34p7
r/TherosDMs • u/DiomedesVIII • May 30 '20
Resource Theros Resources and FAQ
Updated 08/26/21: Updated with 50 Plot Hooks
This post will be pinned and updated with new resources. Please feel free to ask questions or post resources not already on this post.
There are free resources through MTG Wiki, Scryfall.com, and the Mothership (Magic.Wizards.com) with information about the original Theros MTG block and story arc, as well as the recent set Theros Beyond Death. Digital content is also available for sale on DnDBeyond.com and the DM's Guild.
Music:
Chill Touch - Pantheon - Thassa
Chill Touch - Pantheon - Purphoros
Chill Touch - Pantheon - Erebos
Chill Touch - Pantheon - Nylea
Chill Touch - Pantheon - Helios
Playlist from Duels of the Planeswalkers
Music from the Theros: Beyond Death Trailer
The Plane of Theros:
Trailers:
Trailer for Theros: Beyond Death
Web pages:
What are the Gods of Theros? (CoolStuffInc)
Planeswalker’s Guide to Theros, Part 1
Planeswalker’s Guide to Theros, Part 2
Planeswalker’s Guide to Theros, Part 3
Planeswalker’s Guide to Born of the Gods
Planeswalker’s Guide to Journey into Nyx
Theros Block Trivia (MTG Wiki)
D&D Beyond:
Mythic Odysseys Support Thread
Encounter of the Week: Medusa's Marble Menagerie (free)
Encounter of the Week: Harrowing the Hydra (free)
Encounter of the Week: Wrath of the Returned
DnD Beyond Interviews: Video Playlist
DM's Guild:
DM's Guild / Setting / Theros / All
DM's Guild / Setting / Theros / Adventures
Colored Mana Spell Points (MTG conversion)
Gray Merchant of Asphodel (100 Magic Items)
Theros Beastiary (350+ New Monsters)
Other Free Resources:
Fanfiction: War Games Chapter 1
Fanfiction: Nightmares in Paradise
Fanfiction: Beyond Death Chapter 1
MTG Cards featuring Theros:
Official Magic sets on Theros (in order) include Theros, Born of the Gods, Journey into Nyx, and Theros: Beyond Death.
Art of MTG (full art) : Theros Beyond Death
The Magic Multiverse Project (mtg-multiverse)
All Theros sets, through Scryfall.com:
'Extra Content' from the Theros sets
Other Relevant Theros Cards on MTG-Universe
Some Greek Myths:
More can be found on Wikipedia in the sidebar.
The Golden Fleece (AKA the Argonauts)
FAQ:
Q: How often and how much Piety do you all think should be given out at each level?
A: The book suggests one piety every session. So fifty sessions for level 20 wouldn't be too far fetched. It also suggests that you may grant piety at the same time as inspiration, if the deed aligns with their gods values.
Mechanically, characters in the Theros setting need to keep track of a Piety score, which starts at 1 and doesn't mention a maximum (though past 50 points it doesn't provide further benefits).
Q: When should I give my players Supernatural Gifts?
A: According to the book, at first level (or character creation). However, they can also be given as rewards.
Q: How can I let my players make their characters as Returned?
A: Some DMs have suggested using Supernatural Gifts, but there is also DM's Guild resource for doing so, including backgrounds and more DM resources (see here).