I talk about Godbound a lot (free version available here, and the deluxe version available here; free version is complete and has everything you need, the deluxe version just has extra content, it's basically an included splatbook). It is probably my favorite RPG. Therefore I decided it deserves a blog post, so here are ten commandments for running Godbound. The first two, and the tenth, are house rules, and labeled as such; the rest are advice.
Obviously, I'm calling them ten commandments for the joke, but in reality do whatever you want, I'm not your boss.
1 - (House rule) Normal attacks can be defensively miracled by any effect that would make sense to defend against the attack form. The core game states that normal attacks can only be blocked if you can miracle up a specific defensive Gift. This limits player options, creates pressure for players to take specific Words that can defend against normal attacks, and also makes powerful bosses have an incentive to use their least interesting attack; normal attacks from divine opposition usually deal so much straight damage that, unless blocked with a Gift, a character can be killed in a single round with focus fire. Allowing any thematically appropriate miracle to block them fixes these incentives, and it's still a very bad situation for a character to be in if they need to repeatedly block normal attacks without being specialized in doing so, because they're committing Effort for the day and the attacker isn't using any Effort at all. (This is very bad for the defender.)
2- (House rule) Any defensive miracle, defensive dispel, or offensive dispel must be described in terms of its in-world effect. The in-world effect must be able to achieve the desired goal. The action has whatever result and duration the in-world effect would have, with one restriction; defensive or non-damaging actions can't be used to harm worthy foes. (On the other hand, if you're defensively dispelling a fireball with the Word of Fire, sure, go ahead and just deflect it onto some lesser foes.) This helps maintain investment in the world and tension and investment in combat. It also helps keep combat fresh and exciting; you never just attack or defend. You create fog to hide from an enemy, who freezes the fog into spears of ice to cast at you, so you transmute the ice into snow and are unharmed. Everything follows what has come before and creates an unbroken chain of back and forth.
3 - You cannot apply optimizer logic to this game and expect it to work. If at any point you start thinking about a tier list or grading options by color, you have fucked up and you must stop what you are doing immediately. The Words are each the best at the thing that they do. Whether or not you want that thing is up to you, but that's what they do. The Gifts on the page are only examples; you can take a Gift for anything that you could miracle up. If you think a particular Word doesn't have the right Gifts, or its Gifts are too good, take some other ones then, that's your problem. The only "balance problem" in any Godbound book or supplement is Purity of Brilliant Law, and that was just a mistake which was fixed in Lexicon of the Throne; nothing's perfect and mistakes do happen.
4 - You should fight non-divine opposition. Not just have it there to describe it being removed, but actual combat encounters. An ordinary ogre vs a single 1st-level godbound is about comparable to an Easy D&D-type encounter; the godbound is almost certainly going to win, but unless they are extremely combat-focused, they will have to take damage or expend resources to do so. A Small Mob of ogres is a perfectly viable combat encounter for a group of 1st-level Godbound, or a Large Mob of goblins; a Vast Mob of ordinary goblins is likely to defeat the group!. If every combat encounter where you bother to get out the dice is against divine opposition, it makes the world feel much more divine and makes the characters feel less special and less mythic. You need to have an actual fantasy world, not just a bunch of gods and divine beasts in a fighting tournament. If you don't invest in creating a world and making it feel like a world, the players won't invest on their end, and the whole game falls apart from there. Divine level opposition is for special occassions, bosses, and telegraphed things.
5 - The book mentions this, but it is worth reiterating. For Godbound past the first few levels, the question most often is not 'am I capable of doing this'. Because you are. You can force it to happen if you want to. The real question is how far are you willing to go to make it happen. For basically anything in a normal human town or city, you could make people do whatever you want; you might have to kill some people or magically enslave people or burn down some buildings or level 75% of the city, but all of these are within your power. Do you really care enough about your goal to do those things, though? Where are your lines, what are the things you won't do; and what goals will tempt you to break the lines that no one but you can enforce on yourself? Obviously the players should think about this, but the GM should think about it too.
6 - Another thing that the book mentions, but worth reiterating; your characters must have ambition. You must have not only goals, but the drive and willingness to achieve those goals. A group of Godbound don't have the kind of mundane challenges that normal people would; you're never going to struggle to put food on the table or pay rent or mortgages. It's going to get covered. If all you want to do is have a comfortable middle-class life, there's not a whole lot that can stop you. This is not usually a great campaign. You need to have goals, preferably incredible goals commensurate with divinity. You can't just want to be the strongest in a small village; you're already that. You need to want to be the strongest in the universe. You can't just want to build a tower and library in the wilderness; again, you can do that at 1st level. You need to want to build the Tower of Babel, and prevent it from falling down, and store every book in every language ever written. You won't be able to do these things immediately. You might not even be able to start immediately. But you'll be able to think about it and work toward it immediately, and that's the kind of call to adventure that a Godbound party needs. Just as a Godbound character is much more powerful than a starting D&D character, their goals need to be more powerful to motivate them. Godbound characters work and act on a scale layer higher than normal D&D characters; a 'five dungeon adventure' is the Godbound equivalent of a 'five room dungeon'. That kind of scale increase needs to apply to their goals as well.
7 - There is no such thing as flavor text. This ties into commandment 2, but is more generalized. Any description has its logical effect on the world; nothing should be ignored or allowed to violate diegetic precedent or in-world laws. For example, a blast of cold can freeze loose water, and a blast of fire can ignite easily flammable materials. However, this should be balanced by remembering that the characters are divinities, and can control things! A Godbound of Fire can throw a blast of fire that only burns what they want it to burn, because they're the god of fire. If a Godbound of Winter is throwing torches around for some reason, they might accidentally ignite a fire. These forces should be balanced by considering the player's intent and their abilities. As the Godbound of Sword can deal nonlethal blows with a chainsword but a Godbound of Passion cannot, the same logic should be applied to all other effects. All effects, all abilities, and all powers have the logical effect on the world based on what you know about the world and the description of the power's effect in the world; except when the Godbound intends otherwise and has the power and skill necessary to prevent it. By maintaining the normal laws of cause and effect whenever possible, it helps players feel more mythic and more associated with their character's abilities and divinity when they get to ignore them.
8 - The book recommends that the setting be a world on the brink of disaster or shortly after disaster. This is a fine starting point, especially if your party is the kind that needs a bit of a kick to action, but it isn't actually required. It's perfectly viable to play Godbound in a normal, stable fantasy setting. What's important is that its equilibrium is weak enough that Godbound can upset it; which is pretty likely. Even the Forgottem Realms would have trouble maintaining a stable equilibrium against the concerted force of a party of high-level Godbound, the actual gods would need to start stepping in (and if they did it one at a time, max level Godbound might still win). It's perfectly fine to just use a setting that's famliar to you and all the players, as long as you go in with the understanding that canon stops when the first session starts. Everything after that is going to be affected or flavored, or directly caused by, the actions of the players. Using an existing setting can also help with getting players invested into the setting, which in turn helps support their goals and ambitions, and those are both important core parts of getting good gameplay out of your Godbound.
9 - Do you have modules and settings for any OSR or NSR game that you've read and enjoyed, but never gotten to run? Or maybe just haven't gotten to run as often as you like? Use them as minor challenges for Godbound characters! Ever picked up a megadungeon, the kind of thing that consumes a years-long campaign, and you really know you're never going to get through it even if you did manage to run it for a few months sometime? Let some Godbound at it for 1d12 sessions and it'll be at least mostly gone. Godbound can blow through standard OSR setups at vastly increased speeds. This is a great way to implement Commandment 4 (about non-divine opposition); you don't have to change the modules at all. They're a minor challenge to Godbound. Anything that normal OSR characters would do in one session is about equivalent to a long combat encounter for Godbound; you'll blow through most one-shot dungeons in an hour or less of game time. The accelerated pace of gameplay lets you feel your power, but as you rush though because you don't feel the threat, you'll tend to find traps the hard way (unless you have Gifts for it) and draw multiple encounters at once. Then you'll still win and it will be great. There's no drawbacks. (Side note: Some people have historically complained about things like a Godbound character dying to an OSR-style save or die trap as you might find in an unmodified module. Remember that a Godbound can always Commit Effort to succeed in a save, and they can do this after rolling. So if you die to a poison trap, it's because you a) failed a saving throw and b) didn't have any divine power left to save yourself with, because all your Effort was Committed and you kept going on anyway. Godbound are not immortal and if you've spent your entire store of energy, you're still kind of a badass by OSR standards but you are by definition not able to draw on divine power.)
10 - (House rule) XP is not necessary for Godbound. You already need to spend Dominion to level up, which is the result of diegetic actions. You can just remove XP and use Dominion alone to level. (If you want to really go all the way, you can also require that unlocking new Words, instead of costing you Gift points, is done in-world by locating the Word's celestial engine, associated artifact, or other physical item or special location.) This is an example of the systemic flexibility of Godbound; there are very few games that normally use XP where you can say that you can just remove it and it'll be fine. Of course it will change things, and it's up to you if you want that change, but if you do want something to change about the system, it is very likely that you can just change it and it will be no big deal. (For example, I say you don't need XP because Dominion spend is required to level; that's because I think the Dominion spend is more important and valuable to the things that interest me about Godbound. But you could just as easily remove the Dominion requirement and keep XP, and it'd still be fine)
Secret Eleventh Commandment - An it harm none, do as thou wilt. Godbound is a game built on an OSR chassis and cross-compatible with almost any OSR game. It is very, very flexible and resilient. You can basically do whatever you feel like to the system, as long as the group agrees, and it will work out. If someone wants their divine powers to work a little bit differently from the default expectations, make some stuff up and run with it, it's very likely to work just fine. This can be used to simulate specific worlds or abilities, or just to make things different. If you want to use something from another OSR game, just use it, don't worry about converting to make it consistent; it'll work fine. All commandments aside, one of the reasons why I like Godbound so much is this flexibility, because it provides you with a framework that can support basically whatever you want as long as you can fit it into its theming.