In this article series, we’ll be revisiting and reviving the Insomnia project, a book designed to bring horror to your D&D game.
From my experience, actors in a horror movie rarely strut around wearing full plate armor or chainmail. However, Armor Class is simply too fundamental to remove from 5e altogether, so we face an impasse: how do we keep AC while removing armor?
The variant rule that follows is sure to be a controversial one: just give each class an AC calculation. What could possibly go wrong?
It’s worth mentioning that we’re also implementing a whole side system for armor-like suits. Perhaps you might don a firefighter’s heavy coat or a bullet-proof vest to survive your next inevitable monster encounter. We’ll show off those rules in another article.
Variant Armor Class
Replaces Armor
Characters in a modern setting won’t walk around festooned in heavy armor, even modern ballistic armor like that worn by SWAT teams. As such, characters can opt to use the following Armor Class calculation. A character with levels in two or more classes can pick a calculation from any of their classes. Some calculations improve as the character reaches higher levels in the class, as noted in the appropriate column:
| Class | Armor Class (1st Level) | 4th | 8th |
| Barbarian | 10 + your Dexterity modifier + your Constitution modifier | — | — |
| Bard | 12 + your Dexterity modifier | — | — |
| Cleric | 13 + your Dexterity modifier (max 2) | 14 | 15 |
| Druid | 13 + your Dexterity modifier (max 2) | 14 | 15 |
| Fighter | 16 | 17 | 18 |
| Monk | 10 + your Dexterity modifier + your Wisdom modifier | — | — |
| Paladin | 16 | 17 | 18 |
| Ranger | 13 + your Dexterity modifier (max 2) | 14 | 15 |
| Rogue | 12 + your Dexterity modifier | — | — |
| Sorcerer | 10 + your Dexterity modifier | — | — |
| Warlock | 12 + your Dexterity modifier | — | — |
| Wizard | 10 + your Dexterity modifier | — | — |
If you’re playing a class that doesn’t appear on the table above, you can use the following general calculations, based on the character’s armor proficiencies:
| Proficiencies | Armor Class (1st Level) | 4th | 8th |
| None | 10 + your Dexterity modifier | — | — |
| Light Armor | 12 + your Dexterity modifier | — | — |
| Medium Armor | 13 + your Dexterity modifier (max 2) | 14 | 15 |
| Heavy Armor | 16 | 17 | 18 |
Shields
If a character has proficiency with shields, they can use a bonus action to fight defensively, gaining a +2 bonus to their Armor Class until the start of their next turn. To do so, the character must be holding a sturdy object that is not a weapon in one or both hands.
