D&D 5E High Fantastic Races. What are the appropriate weaknesses?

[turnip_farmer]

There's been several voices raised to the gist of 'don't do this', so I just wanted to pop in with a bit of encouragement to OP to ignore them all, in case they're starting to make you question your judgement.

OP asked us for suggestions on how to implement an idea. If you don't like the idea and have how no ideas about implementation, what are you doing here?

"Hi guys, I'd like some suggestions for running my Cyberpunk game."
"Tough. Instead, we're going to explain why we don't like Cyberpunk."

With that out of the way, the classic Elven weakness is iron, so I would probably work with that. Restrictions on armour and weapons they can use, for example.

Dwarfs are not magical (yes, I grew up playing Warhammer), so maybe some restrictions on magic item use? Based on your game that could either be irrelevant or overly punitive, though.

Struggling a bit with halflings. Perhaps disadvantage on Constitution saves caused by hunger? It would, again, be quite campaign-specific whether that mattered at all

 

[Vaalingrade]

There's been several voices raised to the gist of 'don't do this', so I just wanted to pop in with a bit of encouragement to OP to ignore them all, in case they're starting to make you question your judgement.

OP asked us for suggestions on how to implement an idea. If you don't like the idea and have how no ideas about implementation, what are you doing here?

'Is there an opt out option' is not the same as 'don't'

Struggling a bit with halflings. Perhaps disadvantage on Constitution saves caused by hunger? It would, again, be quite campaign-specific whether that mattered at all

Small size is an already existing disadvantage, locking halflings out of weapon choices for 'verisimilitude', which is the greatest disadvantage of all.

 

[Helpful NPC Thom]

I really like the idea of making race more of an important part of your character beyond the ability scores. I think granting racial feats is a splendid idea, and I would impose some disadvantages to counterbalance it. Giving elves fey vulnerabilities is a good example of that, but you want to be careful that you aren't giving the players too much to track. I might also give each character a special Flaw related to their race. There's not a lot of mechanical weight to that, but it's a way to get players into the proper mindset.

 

[turnip_farmer]

'Is there an opt out option' is not the same as 'don't'

Small size is an already existing disadvantage, locking halflings out of weapon choices for 'verisimilitude', which is the greatest disadvantage of all.

'If you would like to use a d10 damage die for melee attacks you cannot use a shield' is the greatest disadvantage of all?

 

[Vaalingrade]

'If you would like to use a d10 damage die for melee attacks you cannot use a shield' is the greatest disadvantage of all?

The problems of a text-based medium. No, Verisimilitude is the greatest disadvantage of all.

 

[Steampunkette]

Humans: Disadvantage against Mind Control effects (Charm, Dominate)
Elves: Double Damage from cold-iron. Even holding Cold Iron burns them, dealing 1 damage per round.
Halflings: Triple Ration Requirements for a Medium character.
Tieflings: Same as Elves but Silver. (A whole race that never uses Silver Coins out of Superstition, too)
Half-Orc: Fear Effects act as an Enrage, instead. They attack the nearest target blindly.
Dwarves: Must drink Booze instead of Water or dehydrate.
Gnomes: Cease to Exist. >.>
Dragonborn: When exposed to more gold than their level x 1,000 must roll a save or start building a hoard.
Half-Elves: Imposter Syndrome.

 

[CleverNickName]

Maybe a good way to assign appropriate "weaknesses" could be done by adjusting the cap on ability scores? It isn't a direct weakness, not a penalty that gets imposed upon a character, but it does move the goalposts a bit for characters at higher levels. For example:

Humans: all ability scores are capped at 20 (PHB standard).
Dwarves: Constitution capped at 22, Dexterity capped at 18, all others capped at 20
Elves: Intelligence capped at 22, Constitution capped at 18, all others capped at 20
Halflings: Dexterity capped at 22, Strength capped at 18, all others capped at 20

And so on.

 

[Vaalingrade]

Dwarves: Must drink Booze instead of Water or dehydrate.

Now I want dwarf fortress dwarves.

Go mad without booze, attract cats, think magma is a proper improvised weapon.

 

[Minigiant]

So Far These are what I've got as my favorites.

Dragonborn
Hoard Instability: You have disadvantage on Intelligence, Wisdom, and Charisma check if in the presence of more gold and gems then you visibly have on you person.

Dwarves
Lullaby of the Earth: You need the earth's murmurs to properly sleep. If you take a long rest aboveground, you are fatigued afterward and have disadvantage on ability checks until you take a hort or long rest underground or surrounded by earth or stoneworks.

Elves
Iron Weakness: You have vulnerability to weapons made of pure iron and take 1d4 necrotic damage when touching or stuck by an item made of cold iron.

Gnomes:
I like @EzekielRaiden 's suggestion but I don't know how to write it.

Half-Orc
Fright or Fight: When frightened, you instead cannot move away form your source of fear and must make spell attacks or Strength weapon attacks at the source if able. You do not have disadvantage on these attacks.

 

[EzekielRaiden]

So Far These are what I've got as my favorites.

Dragonborn
Hoard Instability: You have disadvantage on Intelligence, Wisdom, and Charisma check if in the presence of more gold and gems then you visibly have on you person.

Dwarves
Lullaby of the Earth: You need the earth's murmurs to properly sleep. If you take a long rest aboveground, you are fatigued afterward and have disadvantage on ability checks until you take a hort or long rest underground or surrounded by earth or stoneworks.

Elves
Iron Weakness: You have vulnerability to weapons made of pure iron and take 1d4 necrotic damage when touching or stuck by an item made of cold iron.

Gnomes:
I like @EzekielRaiden 's suggestion but I don't know how to write it.

Half-Orc
Fright or Fight: When frightened, you instead cannot move away form your source of fear and must make spell attacks or Strength weapon attacks at the source if able. You do not have disadvantage on these attacks.

Assuming you want a more simplified version...

Fading Presence: When you roll a 1 on a saving throw against a spell, you become insubstantial for one round. An insubstantial creature is restrained, cannot concentrate on any effect, and cannot take actions that affect its environment or other creatures. Other creatures automatically fail to affect an insubstantial creature with any action targeting it, and can pass through the insubstantial creature's space.

(Alternatively, you could just say that the target is affected by etherealness for one round with some added problems, but I like the above better, as it's more inherently negative than etherealness is.)