Dessert Nomad
Adventurer
It's probably a combination of wanting to avoid defining exactly what metal armor is and who's wearing it for a common cantrip, the fact that it's something that will be used against PCs much more often than monsters so it's really a penalty, and not wanting to sort out a precedent of what lightning effects throughout the game have extra effect against metal armor.The funny thing is, I don’t recall there being a major public outcry about the 2014 version being overpowered. So I’m not sure why they nerfed it in the first place. But, personally, I think I’ll homebrew the “advantage if the target is wearing metal armor” back in for my campaigns.
"What exactly counts as metal armor" is something that came up a lot with the weird 5.0 druid rules that stated that druids "will not use armor or shields made of metal". The best RAW argument I've seen is that armors that say they are metal are metal (so full plate, half plate, splint, chain, chain shirt, scale mail are metal but padded, leather, hide, studded leather, spiked armor, and ring mail aren't), but that also doesn't tell you if there's a way to use alternate materials and how much it costs, and whether exotic metals still count as 'metal' for things like shocking grasp (are mithril and/or adamantine conductive?).
Defining 'metal armor' is something they should still do since they still have Heat Metal in the game - obviously a DM can ad-hoc rule whether a stat block has metal armor and what armor a person can get, but it really seems like something that should have a better starting point.








