D&D - Armor, and the implications of its removal
I'm in the planning stages of a Viking-themed game I'll be running sometime next year, and I'm noticing a nice little progression in the armor types that ends with chain mail. When combined with a silver-based economy that cares more about the weight of the silver over the number of coins you have, that puts a lot of emphasis on looking towards magic for your better AC values, as armor will generally be more expensive and the (typically) highest tiers of armor--namely, plate mail, but also things like splint and banded mails--are simply unavailable for sale or amongst the majority of the enemies you might face.
That magic will most commonly be from the runecaster, probably, since there's a rune available that can be worn like a necklace and improve AC, as well as another that can reduce damage taken. Magic armor will still be--likely even moreso--coveted and sought out by the players.
A PC with average Dexterity can reasonably hit AC 3 (or AC 17 if you're used to ascending values); this assumes chain mail, shield, and a protection rune. Normally AC 3 (banded mail and a shield) is the best a starting PC (with no adjustment from Dex) can hope for in a traditional game.
If you game is based on 5e then making higher tier armor more scarce could have the unintended consequence of making fighters less viable as a class. A level 1 Barbarian (CON: 16 and DEX: 14) with shield have an AC of 17, so they easily get a comparatively high AC early on. Same is probably true for monks (though not as thematic for a viking themed campaign). A lvl 1 wizard (DEX 16) will have an AC of 16 (with mage armor). A lvl 1 fighter with Chain mail and shield would have an AC of 18. That would be the highest they'd get without magic items (or finding the rarer pieces of armor), whereas the Barbarian could bump their con/dex up to 18 each and have an AC of 20 with a shield. Thematically the fighter probably shouldn't start with a chain mail. If they instead started with a chain shirt then they'd have an AC of 17 (give a DEX of 14 and a shield), so not much lower.
So in short, effectively capping the AC of fighters at 18 (without magic) makes the fighter comparatively weaker.
Ah, this is not for D&D 5e, no. I'm using 1e, with descending AC and ultimately different armor values, and Dex--while it does adjust your AC regardless of armor worn--doesn't start doing so until you hit 15.
The progression would look like this, with the ascending equivalent in parentheses.
All of those adjusted by 1 if using a shield. From there, you'd need Dex adjustments, magic armor, spells, or runes to get better AC.
Ah! Not familiar enough with 1e to have an informed opinion on the impact of lowering the effective AC. Currently my group are playing Call of Cthulhu, which has a completely different feel from DnD.
If you want some inspiration settings wise you could look at the swedish rpg "Drakar och Demoner: Trudvang" from 2006. The setting is a fantasy Norse one with an art style reminiscent of John Bauer. Aside from the setting it had a nice mechanic where you aquired equipment packs and when you needed an item (that you hadn't used before) you could roll to see if it was included in your pack (per the GMs discretion). It made it easier to purchase equipment without having to specify precisely what you bought (unless you had a reason to be super specific).
Anyway, good luck on your prep!
Dragonbane is the modern version of Drakar och Demoner, but doesn’t have a rule like that. Perhaps it’ll come out in the Expert rules.
Do all classes get access to heavy armor in 1e? In 2e only warriors and clerics can use them effectively (everyone else uses chain mail or worse) so removing heavy armor would nerf those classes specifically. Clerics can still be effective as spellcasters but I feel like warriors will be unable to play their role effectively.
How are you rolling stats? Having a high dexterity sounds a lot more powerful in this game but you are unlikely to get there with the typical 3d6 roll.
Fighters--and their subclasses--could use any armor, as well as clerics (though druids couldn't wear metal) and thieves (including the assassin), though they got penalties to their thief abilities. Everyone else couldn't wear armor.
That said, there's no paladin, cleric, druid, assassin, or monk here, and four (five with thief) of the seven allowed classes can use any armors.
The easiest modification would be to allow characters to mechanically wear armor, but to have it be flavored as something else. "While this charm is on your person, it fills you with the warm sense of your ancestors looking over you and you gain the benefits of wearing plate"
In my opinion, this undermines the general idea, and it would be weird to me to have such a charm also impose the typical restrictions on movement they have.
That said, it's fairly easy to get to plate equivalent AC; all you need is chain mail, a shield, and one of those protection runes I mentioned, which will put you at AC 3 (17), same as plate mail. Once we start getting into magic armors and magic shields and Dexterity adjustments, it's a lot easier than it might seem at first glance to get from a respectable AC to a very good one.
ETA: Not to mention this idea already exists with the Bracers of Defense.
Of note, the races allowed are humans and trollborn; the classes allowed are fighter, ranger, thief, bard, specialist wizards, berserkers, and runecasters.
Humans are standard, no bonuses or penalties, though they can optionally accept a gift from the Norns during creation, which can be nothing, something good, or something bad.
Trollborn have distinct features but are still visibly human. They get +1 to Str, Con, and Int, a -1 to Wis, and a -2 to Cha. They also have infravision and are barred from being thieves or bards.