D&D 5E (2024) Building A Contemporary Fantasy Setting For 5.5E

[Remathilis]

How fast is the pickup? How much damage does it do if I ram it into the dragon?

Vehicle rules exist already. You just need to create stats for modern vehicles.

Bare in mind, I'm not saying you wouldn't need some new things. You would need to stat new gear, probably add new subclasses, feats and backgrounds. But you don't need to rewrite base classes or combat rules or redo the magic system. You don't need a wholesale rewrite of the PHB, any more than Dark Sun or Theros needed wholesale rewrites of the PHB.

 

[AlViking]

How fast is the pickup? How much damage does it do if I ram it into the dragon?

As long as the characters don't have access to military technology, I don't see why D&D wouldn't work. Yes you have to assume action movie logic for guns (running crouched with one hand raised to cover the side of their head obviously makes them bulletproof), but that's largely because we've never seen someone take a direct hit from a sword.

As far as how much damage a pickup does if it hits a red dragon - who cares? Make it up. Just like if you were piloting a sailing ship and rammed the dragon, or dropped your Daern's Instant Fortress on it's head and activated it as it fell. There are all sorts of things we have to just kind of guess at.

 

[humble minion]

As long as the characters don't have access to military technology, I don't see why D&D wouldn't work. Yes you have to assume action movie logic for guns (running crouched with one hand raised to cover the side of their head obviously makes them bulletproof), but that's largely because we've never seen someone take a direct hit from a sword.

The big problem you'd run in to is that the maths of D&Ds core combat mechanism is built around armour and shields being a major useful factor in combat. You'd need to compensate for that somehow, and all options are non-ideal. Introduce modern-day armour, kevlar vests etc that grant ludicrously high AC to make the maths work? Just go with it and have everyone hitting MUCH more often than bounded accuracy etc assumes? Everyone has some sort of handwavey magic armour or a fiat AC bonus based on level? Just accept that everyone's going to be a high-Dex ranged combatant and that Str is functionally worthless now?

Similarly, there's a heavy emphasis on melee and close-quarters combat in the D&D combat system. Even ranged combat is a bit of an afterthought, there's a lot fewer feats, features, options etc for shooters than there is for hitters, and the balance is probably less good on the whole.

I'm sure its POSSIBLE to do, but the 5e core assumptions don't make it even remotely ideal for the genre.