How do mixed movement modes work with the alternate encumbrance rules?

Question

We use the alternate encumberance rules, where you only can carry your Strength times 5 pounds unencumbered. Per the rules, up to that weight, you can move your speed in a round. When you are encumbered you get slowed down by 10 feet, and when heavily encumbered by 20 feet. If the load is so heavy you only can drag it, your speed gets reduced to 5 feet.

What happens if a character has used some movement, and at that point picks up something heavy that alters their encumberance and speed, especially if it is so heavy they can only drag it?

For a practical example from todays game, a character went down in combat. His fighter friend moved towards him (using up 10 feet of his 30 feet of speed). He already was loaded close to the maximum of his unecumbered carrying capacity of 80 pounds, due to armor, weapons, and heavy sacks of loot. The fallen character with their equipment weighed close to 240 pounds. This meant their own equipment, and the fallen character together, were a load of close to 320 pounds. At that point, with Strength 16, that was heavier than the limit of 16 x 15 = 240 pounds for heavy encumberance, so their only option was to drag them -- that works up to 16 x 30 = 480 pounds.

So, can the fighter still drag his friend? The movement gets replaced then by 5 feet of movement, but not all the movement is available to be replaced any more, as a third of it has already been used up.

Answer 1

The way the rules say

On your turn, you can move a distance up to your speed.

However you're moving, you deduct the distance of each part of your move from your speed until it is used up or until you are done moving.

If you have more than one speed, such as your walking speed and a flying speed, you can switch back and forth between your speeds during your move. Whenever you switch, subtract the distance you've already moved from the new speed. The result determines how much farther you can move. If the result is 0 or less, you can't use the new speed during the current move.

Combined with these rules.

While pushing or dragging weight in excess of your carrying capacity, your speed drops to 5 feet.

If you carry weight in excess of 5 times your Strength score, you are encumbered, which means your speed drops by 10 feet.

If you carry weight in excess of 10 times your Strength score, up to your maximum carrying capacity, you are instead heavily encumbered, which means your speed drops by 20 feet …

So, for your example, the PC is encumbered and so has a speed 10 less than normal. You don’t say what their unencumbered speed is, we’ll call it \$s\$.

They move 10 feet to their buddy. If 10<\$s\$-10 they still have movement remaining.

Picking up their buddy would put them over their maximum lifting capacity, so they can’t do that. However, they can push or drag them which makes their speed 5 feet. Now 5 speed is less than the 10 feet they have already moved so their movement is over.

If you haven’t used your action this turn, you can Dash to “gain extra movement for the current turn. The increase equals your speed, after applying any modifiers.” So, another 5 feet, which doesn’t help because of the new total of 10 feet you’ve already used 10 feet. If you could Dash again, through the Fighter’s Action Surge or the Rogue’s Cunning Action, say, you could get another 5 feet which you could use.

You need to remember that how far you have moved is never subtracted from how far you can move. These are always two seperate numbers that are constantly compared to one another - if the first is bigger than the second, you can continue to move, if it isn’t, you can’t. How far you can move can change up or down, how far you have moved only ever increases.