I've no idea how encumbrance could be challenging, but I did hear of a game that abstracted weight a bit to make encumbrance simpler. Instead of a pound weight, all common items were weighed in stones; for example any one handed weapon of similar size to a long sword weighs 1 stone.
Of course this wasn't D&D and I've never played it, but it sounds like a great balance between reality and abstraction.
One of the posters here, who I remember as SuperDan due to his home page, had this stone encumberance rules for DnD, which I adopted for 4e. One of my campaigns us a 'search the world', and more engaged in some of the more mundane challenges of adventuring. So far the game has goine very well and the ruling has caused some seriously hard choices.
Here are the rules as they are currently being used:
[sblock]Encumbrance is an approximation of how much stuff your character can carry before it gets to be difficult. Rather than pure weight, encumbrance takes into account bulk, weight, and manageability. Encumbrance is counted in Stone, 1 of which is roughly equivalent to 15 pound.
Your character can carry a number of Stone equal to your Strength score plus your strength modifier without any problems. This is your Encumbrance Cap (EC). One quarter of that, rounded normally, is your encumbrance value (EV).
If you carry more than your EC in Stone, your incur a -1 penalty to your Speed, AC, Ref defense, and skills that are related to Strength or Dex.
This penalty increases exponentially for every additional Stone weight equal to your EV.
Example, Joe fighter with a strength of 14 has an EC of 18 and an EV of 4.
Joe suffers a -1 penalty if he carried more than 18 Stone but less than 23.
He suffers a -3 penalty for carrying more than 22 and less than 27. Etc...
So, now that you know all that.. how do you weight equipment? It's very simple.
Weapons weigh 1/2 stone for daggers, 1 stone for one handed weapons like a long sword, and 2 stone for two handed weapons.
Add 1 stone for a weapon with the reach property.
Worn Armor and shield weigh their mundane AC bonus in stone. For instance leather weighs 3 stone and chain weighs 5.
Halve the value if the armor or shield is carried.
Coin, of any denomination, weigh 1 stone per 50 coin. Divide as appropriate.
Rope weighs 1 stone per 50 foot.
Kits, like Thieves kits or ritual component kits, weigh 1 stone.
A set of clothing, a torch, or a bedroll weigh 1 stone.
A waterskin that carries enough for 1 person for one day weighs 1 stone.
Trail Rations for two days weighs 1 stone.
Tinderbox and the like weight 1/8 stone.
From this list, you should be able to swag weights on all other items
Bags halve the weight of items carried inside, but have a limit to what can be put in them. It takes a move action to retrieve an item from a bag.
Small bag can carry 1 stone, large bags can carry 2 stone.
A small backpack can carry 4 stones and a large backpack can carry 8 stones.
But wait, there is more!
Size matters, as do extra legs. Each of these factors modified the creatures EC by 4. Why does this matter? Pack horses! They have a strength score of 10, but are Large size and have 4 legs. This means their EC is 18..
and can carry 270 pounds without a problem!
Of course, size also goes the other way. If Joe Fighter was a Halfling, his EC would be 14.
What does this mean to you?
Well, most characters will have plenty of room to carry their main equipment and a pack.. but that's about it. Pack horses, wagons, etc will be of great use. Especially if you plan on looting any dead bodies along the way.
So, mark down your EC and EV. Mark next to your equipment how much it weighs in stone and do some simple math.
Oh.. and just incase, divide your characters weight in pounds by 15 and write that down too.. who knows if you will need to be carried!
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