My 5e Homebrew Mechanics & Rules for Eberron

I recently ran 9 levels of Dungeons & Dragons 5e for my home game, and as this was my second long form campaign (first one was here) I found myself starting to custom make different mechanics for different situations that came up. I’m sure not all of them were great, and most of them were not setting specific, but if you’re looking for some new homebrew rules, this might help. Also, very few of these are originally mine. Many of these are common across the internet, some are a cobbled combination of multiple ideas, so I don’t take credit for any of these wholly originally.

Eberron and Campaign Info

Some things you should know going in, Eberron is a Pulp-Noir world, meaning that you can go from grizzled streets of the big city tracking down crime bosses, to sword fighting on flying ships crossing the continent. Also, it’s incorrectly seen as steampunk, because there are robots, speeding trains, and airships. It’s not actually steampunk, but it has many of the same tropes.

There is a huge post-nuclear fallout wasteland in the middle of the continent called the Mournland, that only killed/mutated life forms, and didn’t necessarily harm building materials, so you can travel into this highly dangerous area to search for untold riches.

Travel Survival Checks

My players liked spending table time on travel and survival, which is tough, because the world is so inhabited, that you don’t spend much time travelling through the wilderness. Most travel is done on a lightning-powered train, or at least on a well traveled road. However, when you do go between large stretches of land, I wanted something to do rather than just Redline it.

So first, we are going to determine what is being rolled. Most parties are at least 3 people, so I split up the travel checks into 3 jobs. The first is a Navigation check, the second a Food/Water check, and the third a Threat check. If your party includes a Ranger, then the Ranger can pull off all three. Otherwise, everyone picks a skill that they use for this job. Survival is the obvious one, maybe Perception, Investigation, Insight, Medicine, or some others, but really if the players can come up with a decent reason to use something else (maybe History) then I allow it.

The DC is 13, unless there is something like bad weather that might increase it, but I usually stick to 13, because it gives a Success:Failure ratio that I felt worked well.

If the Navigator fails, it adds travel time to the journey, as they get the party lost. If the Food Scavenger fails, then they have to start to use their trail rations and those are a limited resource. If the Threat Watcher fails, then we have a fun random encounter of some sort, usually a monster or group of monsters that are looking for an easy kill, and will run away. Remember to throw a tough monster at them, because if they know it’s their only fight of the day, they are going to use all of their coolest abilities, or go “Super Nova” as it’s sometimes referred to.

Between Levels 1-5 I have them roll those checks each meal time, Levels 6-10 I have them roll it once a day, Levels 11-15 I have them roll it once for the whole journey, and Levels 16+ I only have them roll it for narrative reasons. This is because things that are tough at lower levels because meaningless at higher levels. I never roll to watch for danger at night, because in Eberron it’s implied that there are plenty of Inns alongside the road, specifically the Gold Dragon Inn, that the party rarely can’t make it to one within a days travel.

Combined Initiative, Mostly

The way Fifth Edition Action Economy was designed, is that if any side of a fight has fewer combatants than the other, that side is at a significant disadvantage. So for a 3 PC party, the average enemy side should have about 3 enemies. Because of this, I as the DM have three times as many turns as the party, and frankly I don’t love that. So, for Like-Monsters (monsters that are essentially identical to one another) I will just roll Initiative once for that group, and they all go together. This is a pretty common solution many DMs have to keeping track of all the monsters and speeding up combat.

Mostly. There was one time when I did not follow this rule, and it’s when I wanted the monsters to be annoying. Stirges, if you don’t know, is basically a cross between a bat and a mosquito. It takes it’s first turn to bite you, and the second turn to suck out your blood. If it pulls 10hp of blood, it flies away full. In order to take it off after it bit you, you must use an action to pull it off, as opposed to attacking. So, I rolled for each Stirge to go on it’s own turn, so that a Stirge would bite, a PC would pull it off, instead of attacking, and immediately after another Stirge would bite. Do they attack the ones in the air, or do they grab the ones that are biting, so they don’t get the free damage next round? It’s incredibly annoying, in the best way.

Mournland Mechanics

Remember that post-Nuclear fallout region I mentioned above? Well, it’s a magical nuclear, so it affects all magic done within the Mournland. When the magic bomb went off, it instantly killed all living things. Anything that has wandered it’s way through the wall of orange-gray mist has become mutated and extreme. This is a country-sized piece of land that is high risk, high reward.

Wild Magic

I wanted to emphasize not only that doing magic is dangerous here, but that the longer you stay here, the more dangerous it becomes. So all spells in the Mournland have a chance of having a Sorcerer’s Wild Magic Surge. Every time a spell is cast (not an ability or Channel Divinity), in addition to the spell casting normally, the spellcaster also rolls a flat 1d20, and their DC is 10+ (amount of days spent in the Mournland). If they succeed that DC, then nothing besides the spell happens. However, if they fail, then they also roll on the Wild Magic Surge chart. So on the first day there is a 50% chance of a Magic Surge, but by the 10th day, if the party is still there, every single spell cast will have an unexpected consequence.

Mournland Healing

I also wanted there to be an effect on their ability to heal in the Mournland. This makes things more difficult, because I wanted the Mournland to be scary to the players, as well as the characters.

  • Healing potions are half as effective
    • Except for healing potions made/found in the Mournland
  • Short Rest Hit Dice are half as effective
  • During a long rest you do not fully replenish your HP, instead you must roll the remaining Hit Dice you have, and those are effective as normal.
  • Hit Dice fully replenish, as opposed to half, because you have to use them all to sleep, I don’t want you to only have half as many the next day.
  • Goodberries each do 1hp, and are thus not affected because you can’t do .5 HP, and Lay on Hands Works as normal because it’s not a spell.

Mournland Dragon’s Blood

In Eberron, there is an addictive narcotic called “Dragon’s Blood” which normally only affects people with “Dragon Marks,” a rare birth affect that few PCs tend to have, as it comes with some mechanical abilities, but a ton of narrative responsibility. But with a Noir genre, I wanted narcotics to be part of the story, so I adapted Dragon’s Blood to have an additional affect if you are in the Mournland.

First of all, Dragon’s Blood heals in the Mournland like an unaffected Healing Potion, but has a chance of addiction and overdose.

  • Black Dragon’s Blood heals 2d4+2 (50g)
  • Blue Dragon’s Blood heals 4d4+4 (200g)
  • Red Dragon’s Blood heals 8d4+8 (2000g)

In addition to the healing, it comes with a feeling of euphoria, and Advantage on all Saving Throws for the next hour. The idea is that I want players to want to rush back into danger once they’ve taken it, and see it as a very helpful resource against the effects of the Mournland.


Note: This is not an attempt to create a realistic depiction of chemical addiction, but a game mechanic to represent the standard fictional narrative. Any offensive or insensitive implications is unintentional.

Each time someone takes Dragon’s Blood, the must make a DC15 Constitution Saving Throw or gain 1 Level of Addiction. The Advantage to All Saving Throws granted by drinking Dragon’s Blood DOES NOT apply to the Save against Addiction. The PC is NOT told what they are rolling for, or the whether or not they succeeded. Each time you take Dragon’s Blood after gaining a Level of Addiction, you must roll the Saving Throw again or gain an additional Level of Addiction.


Also, every time that you drink Dragon’s Blood, you must roll a 1d6. You must roll a number equal to or higher than the total amount of times you have drank Dragon’s Blood within 24 hours. This means that the first time you roll, you’re guaranteed to succeed, and the 7th time you roll, you’re guaranteed to fail. If you roll too low, you Overdose.

  • If you Overdose, you must roll on the Short Term Madness Chart, which will last until you are sober.
  • If you Overdose at Addiction Level 3, roll on the Long Term Madness Chart, which will last until you are sober.
  • If you Overdose at Addiction Level 7, roll on the Indefinite Madness Chart, which will last until you are sober.


If you don’t take more Dragon’s Blood within 24 hours, you begin to suffer from Withdrawal.

“You have an excruciating headache. You begin to have an intense need for more Dragon’s Blood.”

Whenever you suffer Withdrawal, you take 2d6 psychic damage per Addiction Level.

Breaking Addiction

Each time a creature Addicted to Dragon’s Blood suffers from Withdrawal from not taking another dose, they can make a DC14 Constitution Saving Throw to overcome the Addiction. If the creature has two or more Levels of Addiction when making this Saving Throw, the DC for the Saving Throw is increased each time by 1. The first time you attempt to break your Addiction, the DC is only 14, but if you have to break a Second Level, the DC is 15, and so on.

On a successful Save, the creature’s Addiction Level for that drug is decreased by 1. The PC is not told what their Addiction Level is. When a creature has no Addiction Levels remaining, they are completely freed from Addiction, and considered to be Sober, and a PC is told they are now Sober.

You can only roll to break Addiction once per day, at the same time of day as you last took Dragon’s Blood.

Searching for Someone

If you go to an unknown city, and are searching for a specific person within, here is a fun way to find that person, and also learn more about the city.

We are going to run the search as a Skill Challenge that you cannot fail.

If you are unfamiliar with Skill Challenges from 4e, Matt Colville can tell you more, but the gist of it is that you have to roll a series of Skill Checks, looking to get a total number of successes, without any one PC using the same skill twice.

So, the way I ran it, was the DC for the Skill Challenge was 12, and they needed to get a total of 6 successes, or about 2 per PC. If you have a bigger city you’re searching, you can require more successes, or if you are less familiar with the city you can increase the DC, but I thought 6x12s was a good quick pace.

With each attempt, the party learned something new about the city, some kind of lore, factions, notable landmarks, etc. If they succeeded, it was one step closer to being done, and the exposition, however if they failed, there would then be some kind of consequence regarding that specific lore. If they learned about a faction, perhaps they start a random encounter with someone from that faction, if they learned about a notable landmark, perhaps they got lost and it took more time to reorient themselves within the city. Several options there, and the DM can actually go through a bunch of cool stuff they know about the area.

Buying/Selling Magic Items

Magic items are SUPER common in Eberron, and in a city like Sharn, which is essentially D&D New York, you can buy pretty much anything. So instead of a price range like the DMG offers, I wanted to find a specific price, which includes wiggle room for bartering with the vendor, or searching around for a lower price. While I love to roleplay with my players, I’ve never enjoyed roleplaying as a vendor, because besides a Persuasion check, the tools given to PCs usually involve violence, and I don’t want to go down that road as the default.

Base Price by Rarity

  • Common (1d6+4)*10g readily available in towns
  • Uncommon 1d6*100g readily available in cities
  • Rare (1d6+4)*100g
  • Very Rare (2d10)2500g
  • Legendary (1d6+1)*25,000g


  • Single Use Base*.5 (Such as Potions or Scrolls)
  • Charged Base*.75
  • Permanent Base*1
  • Attuned Base*1.5


Either a DC10 Charisma (Persuasion) OR Intelligence (Investigation) check. This represents either haggling the price down, or finding a cheaper seller.

For each result above 10, subtract 5%g off the price. If you roll below 10, you do not get a discount. If you roll a Natural 1, the item becomes unavailable, either because you accidentally insulted the vendor, or they sold it to someone else first. If you get a 20, that would make the price 50% off, and you can’t get much better than that.

There were items that were not readily available are still available to purchase by a vendor, but not at that moment. You can order an item, where it can either be shipped from another town, or can be custom made. Either way, if you are trying to purchase an unavailable magic item, it will take an amount of days equal to the (Price of the Item in gold)/5 if purchased through an amateur, or (Price of the Item in gold)/10 if purchased through a professional.


We are going to start at 50% of the Price, because Vendors need to make a profit.

Then, just like with buying, we are going to make a DC10 Charisma (Persuasion) or an Intelligence (Investigation) check, and for each result above 10, you add 5% of the price you can get, either by talking up the item, or finding another vendor who is willing to spend more to get the item.

Skill Checks

This was not me, but from, and every time a player wanted to roll to see what they knew about the monster, I would run them through this list.

What skill do you roll for?

  • Arcana / Aberration, Construct, Dragon, Elemental
  • Nature / Beast, Fey, Giant, Humanoid, Monstrosity, Plant
  • Religion / Celestial, Fiend, Ooze, Undead

How much do you know?

  • If you roll a 10, you know the creature’s name and monster type
  • 10 + half the creature’s CR = 1 Useful Thing
  • 10 + the creature’s CR = 2 Useful Things
  • For every 5 above the 10 + the creature’s CR a character gets, they get another piece of useful information

What counts as “Useful Information”?

  • Challenge Rating
  • 1 Weakness (if any)
  • 1 Resistance (if any)
  • 1 Immunity (if any)
  • Average HP
  • Average AC
  • Best or Worst Saving Throw
  • Skills
  • Special Senses
  • Special Abilities
  • Special Attacks
  • Number of Attacks per turn
  • Attack Damage Type

More Fun Stuff

None of these are full systems, but definitely little notes that made my game more fun.

Whenever a player rolled a Critical Success or Critical Failure, instead of any standard result, I would roll on a chart to see what unique thing happened. Sometimes it would be movement related, or losing your weapon which requires an action to retrieve, or some environmental interference. They weren’t all based on the character’s skill, but just something lucky that happened in the fight.

Whenever I ask for a skill check outside of combat or a Saving Throw, I first ask if anyone is Proficient in that skill. If so, only that character can roll, because I like Niche Protection, or avoiding Dogpiling in my game. If no one has proficiency, then I open it up for anyone like normal.

Eberron has an addition to the standard Personality Traits, Ideals, Bonds, and Flaws, called Debts & Regrets, which gives your character not only some negative aspects of themselves, but ones specifically that the DM can use to create more tension. I plan on having Debts & Regrets be part of every character creation session I have for my players for the rest of time. I love it so much.

Matt Colville, who I’ve already linked to twice in this article, has two books which I found amazing for more Grande play, called Strongholds & Followers and Kingdoms & Warfare. The ideas in those books follow two sets of ideas. Strongholds is about your party have a home base that is more than just a house in a town, but a Castle/Tower/Temple/Tavern, and the inherent political results of that. Followers is about having another, younger, adventurer pledge themselves to you, like Batman and Robin. Kingdoms is what happens when your Castle begins to have a town form around you, and suddenly you are a noble ruler. Warfare is when you have so many people pledged to you that you can send them into battle on your behalf. I piecemealed those systems in ways that were helpful for my game, and they are all just modular enough that you can really be creative with it.

These last two aren’t really rules, but more minigames. In the Eberron setting book Rising From the Last War, they have scattered throughout newspaper clippings from different newspapers about different topics, which gives you several conflicts to think about, and enhances the idea that there is no “right” opinion, that everything you hear is just a point of view. Well, I grabbed those newspaper clippings, and whenever a session was about the same topic as one of those clippings, I would send it to my players the morning before the session, to give them a spoiler-free hint at what was coming, get them back in the headspace of our world, and also maybe show them the opposite viewpoint from the one they were getting from their trusted NPC allies.

Lastly, a few of my players decided they weren’t orphans raised into this life by force, but people with jobs, and so they would write letters back home. Then, a session or two later, I would write them back, and print off the letter and hand it to the player. Each character they would write to would have their own font, some had watermarks of their family/clan/boss on it, and some would be more casual and familiar, while others were more informational and expositional. It was a lot of fun, no letter was more than a page long, and my players would love to ask when they got back to town “do I have any letters?” It was a fun minigame that we all loved to do, and it didn’t take any time away from the game, but gave a more honest look into these character’s lives and backstories.

There is a lot here, not all of it will be useful to you, but I hope some of it inspires you to create your own ideas. “Absorb what is useful, reject what is useless, and add what is uniquely your own.”

What is a cool homebrew mechanic that you’ve added to your game? Let me know in the comments below!


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