Another take on weapon and armor degradation

I won't go too far in saying that dungeon crawling in D&D is basically as much a game of exploration and interaction as it is a game of resource management. Indeed, the more time passes in a dungeon, the more turns are accumulated, and the more torches burn, fatigue lurks, spells are exhausted, and the pressure of wandering monsters is strong.

Weapons and armor are not part of this resource management, so here are two simple rules that allow weapons and armor to get damaged with time. 

Damaging armors

Each time an attacker roll a natural 20 against a player character, the PC's armor lose 1 point of AC until repaired by a competent craftsman.

Damaging weapons

Each time an attacker roll a natural 1 when attacking, his weapon suffers some damage and is down to the previous dice type. A d8 sword become a d6 sword; a d6 mace become a d4 mace, and a d4 dagger is broken. A competent craftsman can repair the weapon for 20% of his base price by dice type lost.

And if it's a magic item?

Maybe the magic items cannot be broken that way? GM choice! If they can, roll a d6. If the result is less or equal than the magic bonus of the item, there is no loss. If it's superior, the item is damaged.

Another take on shields

In Dungeons & Dragons, shields usually only add one point to the AC. This can be a problem when you want to play in an ancient style. Indeed, in ancient times armor was generally lighter and less covering than in the Middle Ages, which made the shield even more important to make up for the weakness of the armor.

Think of Roman armies, Celtic warriors, and Greek hoplites: they all rely heavily on their shields, and the rules don't allow it.

Based on the principle that the lighter the armor, the more important the shield is to a fighter's fighting style, it would be possible to adjust the bonus to AC that a shield provides based on the armor worn.

Worn armor: Shield AC

• No armor: +4
• Leather armor: +3
• Chain mail: +2
• Plate armor: +1

Thus, a fighter wearing lighter armor will still be able to get away with it, even if he is less protected than a fighter in heavier armor.