Inventories and Encumbrance

 This is a bit less of a setting-specific post, but it is one of the few house rules that I will be using for King of Kings. I find that resource management is a very important part of the game, something which adds an important element of pressure on the players to really make their decisionmaking and exploration feel impactful. Well, this is something that plenty of other people have already said before. Here I'll just be describing my encumbrance rules so I can have them all in one place.

So that my inspirations can be openly available (and so I can link to other posts on this topic that I think are interesting and useful):
Mechanics for Resource Management Part 1 and Part 2
Across the Clones - Encumbrance
This compilation of resource management related posts from DIY & Dragons
Presenting the Only Good Encumbrance System
HMS Apollyon Exploration Rules

Okay, so to begin with: King of Kings is going to use slot-based encumbrance (rather than pound/stone/coin based encumbrance) where slots are only considered for significant items. This system of abstracting encumbrance away from the nitty gritty numbers of measuring specific weights of items allows it to have a more readily apparent impact on gameplay, with how it forces player decisionmaking and makes for easy encumbrance tracking.

Player characters have a number of inventory item slots equal to 10+STR modifier (modifier listed below):
3: -3
4-5: -2
6-8: -1
9-12: 0
13-15: +1
16-17: +2
18: +3
This allows for inventories ranging from 7 to 13 slots in size. This differs from the encumbrance system that I have typically used in my games up to this point. Normally, I have had the number of slots equal to the character's STR score, with some modifications based on race perhaps. However, this has oftentimes ended up with characters not interacting with the encumbrance system in a significant way, primarily because of just how high the values were oftentimes! Characters with very low STR scores simply didn't bother picking anything up, while characters with higher STR just never had to worry about it. By bringing it down to a more bounded range, it equalizes the system across all characters.

The first three of these item slots are "quick-draw" slots, items and equipment that the character has close on hand and can be pulled out at a moment's notice. During a combat encounter, items in the quick-draw slots can be used no problem. Items outside of the quick-draw slots require at least one round to retrieve (where the character is not doing anything but searching for that item), and due to the chaotic combat situation the character must roll 1d20 over the item's slot number in the inventory in order to retrieve it. If they fail this roll, they may attempt again, but it is very likely that enemy combatants will have noticed their helpless searching and decided to target them.

Fighters have a potential maximum of five quick-draw slots, allowing them to have more weapons/shields/etc with easy access. For slots four and five, the fighter character can choose whether they are quick-draw slots or normal item slots.

A character can carry up to their maximum amount of item slots without becoming encumbered. Going over the slot maximum encumbers the character, slowing them down and making them clumsier. 10 items over makes you heavily encumbered.

Encumbered: Act last in initiative order, -1 to all rolls, 50% chance of drowning, considerably slower than unencumbered characters for purposes of chases and retreats.
Heavily Encumbered: Act last in initiative order, -3 to all rolls (other than damage rolls), 100% chance of drowning, will always be captured in a chase unless items are abandoned, -2 to AC, cannot disengage from combat.

Specific Item Rules:

Weapons
Weapons are categorized into Light, Medium, and Two-Handed. Light weapons take up half an item slot (so two daggers take up one item slot), medium weapons take up one item slot, and two-handed weapons take up three item slots. Examples of light weapons include daggers and slings, examples of medium weapons include most swords and maces along with shortbows, and examples of two-handed weapons include large swords and longbows.

Ammo
A quiver of arrows or crossbow bolts takes up one item slot. For mundane missile weapons, the specific amount of arrows need not be tracked; it is assumed that an adventuring character has brought enough for their purposes, as long as they have "refilled" the quiver by paying for the associated price on returning to a settlement. A quiver must be in the character's quick draw slots in order to be used in combat. Special ammo should be tracked, with 20 such ammo pieces taking up one slot.

Armor
Armor is categorized into Light, Medium, and Heavy (or, to use more traditional terms, Leather, Chain, and Plate). Light armor takes up two item slots, medium armor takes up four, and heavy armor takes up six. Shields take up one item slot, and must be in the character's quick draw slots and be held in hand to receive the AC bonus.

Coins, Gems, and Treasures
Most small treasure items are not individually important enough to be considered to fill an item slot. 100 coins, gems, or small treasures occupy one item slot. 

Spellbooks and Grimoires
A book of magical spells must be put in the quick draw slots and be held in hand to be used. A single spell book takes up one item slot.

Torches and Lanterns
Three torches or one lantern take up one item slot. For torches or lanterns to provide light, they must be put in the character's quick draw slots and be held in hand. Five units of lantern fuel take up one item slot. A torch or lantern provides enough light for three people to see.

Pack Animals
Items can be stored on pack animals for travel and transportation. Typically, a pack animal or group of pack animals is left outside of the dungeon, but a small pack animal (mule) can be brought into a dungeon or other adventure location. The number of slots of items that a pack animal can carry varies. A mule can typically carry 10 slots of items, while a larger horse or camel can carry 15, and an elephant or giant lizard can carry 20.