When is fall damage divided between creatures using Tasha’s rule?

Tasha’s Cauldron of Everything offers the following rule:

If a creature falls into the space of a second creature and neither of them is Tiny, the second creature must succeed on a DC 15 Dexterity saving throw or be impacted by the falling creature, and any damage resulting from the fall is divided evenly between them. The impacted creature is also knocked prone, unless it is two or more sizes larger than the falling creature.

However I am unclear how this would relate to resistance, the Monk’s Slow Fall, and other damage reducing features.

The rule says "any damage resulting from the fall is divided evenly between them" but it doesn’t specify whether that damage is split before or after damage reducing features.

Is the damage divided between the two creatures before or after damage reducing features are calculated?

What action do I need to fall prone

I am looking for information what action I have to use when I want to go prone like lay flat on the floor. I can as a swift action stand up from prone and want to duck behind a table stand up shoot fall prone again. Just in case it is a swift action, can I interchange a swift with a move action? So I can use my swift to stand up, a standard to shoot and a move to fall prone?

Does the spell Feather Fall prevent damage from falling down stairs?

Inspired by this Q&A: How to handle falling down stairs?

Feather fall says:

Choose up to five falling creatures within range. A falling creature’s rate of descent slows to 60 feet per round until the spell ends. If the creature lands before the spell ends, it takes no falling damage and can land on its feet, and the spell ends for that creature.

It has a casting time of 1 Reaction:

which you take when you or a creature within 60 feet of you falls.

In my answer to the above Q&A, I document three (stair) cases where the characters can fall down stairs and take damage.

From Tales from the Yawning Portal:

From Rime of the Frostmaiden:

From Rise of Tiamat:

In the example from Yawning Portal the word "falls" is used to describe our descent of the stairs. In the latter two examples, the word "tumbles" and the phrase "sliding and tumbling" are used instead. As noted in my answer to the linked question, the module guidance for falling down stairs is very similar to the usual rules for falling.

Does feather fall work to prevent falling-down-stairs damage?

What are the rules for a long fall into water? [duplicate]

Normally when a player falls they take 1d6 bludgeoning damage when they hit the ground per 10 foot they fall.

Are there any RAW for a player hitting water? At what height does hitting water in DnD become dangerous. In reality if you hit water from high enough it is the equivalent of hitting concrete and a I imagine from even a safe hight a player that dives badly may hurt themselves?

Does hideous laughter make a flying foe prone and cause the foe to fall?

A witch that’s using the flight hex to fly 20 ft. up in the air fails her saving throw against my halfling bard’s hideous laughter spell. The spell says that an affected creature

collapses into gales of manic laughter, falling prone. The subject can take no actions while laughing, but is not considered helpless.

Does the witch become prone in the air? Does the phrase take no action mean the witch falls to her death, grappled and subsequently slain by her own foolishly placed black tentacles?

Which year in Dale Reckoning did Elturel fall?

According to Baldur’s Gate: Descent into Avernus, the Companion was summoned in 1444 DR, the Era of Upheaval.

In the relevant contract, it said that Elturel was doomed after 50 years from then.

That means the Fall of Elturel actually took place in 1494 DR, the Year of Twelve Warnings.

However, the Baldur’s Gate Gazetteer in the same module describes the city as of 1492 DR.

Interestingly, in the early-access version of the video game Baldur’s Gate 3 made by Larian Studios and approved by WoTC, which is a sequel to Baldur’s Gate: Descent into Avernus, the current year seems to be 1492 DR. To verify this, you could go north of the Risen Road to find a Tollhouse inhabited by some self-proclaimed Paladins of Tyr. In the basement, you will find a Tollhouse Ledger on the body of a dead Toll Collector, which states that the current year is 1492 DR.

Therefore, canonically, the event took place either in 1492 DR or 1494 DR, as far as I can tell. Has anyone settled this discrepancy? Which year is it?

Can a creature with wings choose to fall to get down faster?

A dragon flies at 4000 feet of altitude and needs to get to ground level as fast as possible.

With a double-move and a fly speed of 200, it can only move 400 feet per round.

But, can it choose to stop flapping its wings and fall (I would assume maybe 500 or 1000 feet per round), and then use the Fly skill to negate the 20d6 of falling damage when it hits the ground?

Feather Fall Spell in 5E – Target Validity Issues?

Couldn’t find an answer to this in my reading of the source books nor on stackexchange. My players were engaged in an encounter in which enemies were able to manipulate air to "gust" them off a cliff. They did recognize that they needed to stay away from the edges but started to lose the battle because of pretty sour rolls. They decided they would leap from the cliff knowing that the sorcerer had the Feather Fall spell.

Feather Fall states: "Choose up to five falling creatures within range. A falling creature’s rate of descent slows to 60 feet per round until the spell ends. If the creature lands before the spell ends, it takes no falling damage and can land on its feet, and the spell ends for that creature."

Because of this targeting restriction, the spell could not be cast unless someone was already falling. As this takes a reaction, there seems to be no way to (prophylactically or otherwise) have the group under the spell if they all decided to jump in the same round of combat. In fact, it seems like it would take 5 castings (party of 5) over a series of 4 or 5 rounds to effect this strategy (with the sorcerer going last), which meant certain doom. I decided to call the session (it was time) to give me a little time to investigate this, but I basically told them there was no way I could see saving the party via feather fall. They were quite dejected considering they/he thought that Feather Fall could be cast as a proactive spell so that they could all jump safely on their own turn.

Can I confidently confirm that I have interpreted this right, whether RAW or RAI?

Can a flying character choose to fall, and then use a reaction to stop falling before hitting the ground?

As a flying character there are a few scenarios that I’d like to know are valid/RAW, invalid, or up to the DM.

Assume in these scenarios that all characters fall at 1000ft/round (this is not up for discussion (no matter how strongly you feel about it) as my DM has made this ruling.) Also assume the fall is intentional (on my turn/not done by an enemy or enemy’s turn).

  1. Fly at 1,005ft, fall (drop prone?) in 1 round (1000ft), next round recover (stand up from prone), land safely or continue to fly.

  2. Fly at 600ft, fall, to 60ft recover to fly normally.

  3. Fly at 600ft, fall, to 60ft cast feather as a reaction to falling. This scenario could also include carrying a halfling (600ft), then dropping her, and she can cast feather fall (as a reaction) 60ft before hitting the ground.

Feel free to add additional cool scenarios that could work. Or if a scenario doesnt work, what would be needed to make it work.

If possible please use citations, especially if any of the scenarios are invalid/against the rules.