Good. Since we (at least) agree on how the official rules work, now we can discuss how absurd they are IMO. While you are correct that examples exist where you would get shot first, there are also examples where the lever is pulled. Since it could go both ways, why don't the rules reflect that? How could these scenarios never arise in play testing and if they did, why rule it in such an ambiguous manner?
Consider what you wrote: "if he was moving onto the trap door and that was your trigger, you could drop him then." So, the reasoning here is that because he was moving and not attacking, your reaction is faster? He is moving when he draws an arrow to shoot, takes aim, and fires. How is that faster than him walking, or you pulling the lever?
There are no speeds for actions, so unfortunately it comes down to the wording of the trigger--which is sad IMO since the intent is clear and it becomes a case of word-smithing.
Thanks. I was hoping it would be a clear example. Now we are just talking semantics. Obviously the intent to pull the lever before the attack is there either way. Has D&D gotten to that point? Where wording is so nit-picky that it causes such strange results?
Your idea of stopping the action and rerolling initiative in this case would work, but that is a DM deciding how to proceed. Like many of the rules in 5E, perhaps it was left this way to create options for the DM/table to use as they see fit. I know other editions had so many rules to make such situations overly clear and they wanted to avoid having a horde of rules.
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Same situation except now I am a player as well (new text in italics):
A bowman is standing over a trap door in the floor and you have your hand on the lever that triggers it. He is holding his bow, but his arrows are still in his quiver. He has valuable information, so you don't want to just trigger the trap and possibly kill him. I am there ready to fire my crossbow at the guy if he moves at all. You have won initiative and are acting first. I am second. The bowman is last:
You: I tell him not to attack or I will pull the lever.
Me: If he moves at all I am just going to shoot him with my crossbow.
DM: Ok, so you are Readying your action to Use an Object, the lever, if he attacks. And you are Readying your attack with the crossbow if he moves.
You: Yep. I know I could interact with it for free now, but I don't want to do it unless I have to.
Me: Sure shooting! *laughs
DM: Sure, he shoots you then.
You: What!? Wait, don't I get to pull the lever first?
DM: You would think so, huh? But since the triggering action was his attack, and your readied action doesn't take place until after the triggering action, he still gets his attack against you.
You: That can't be how it works!?
DM: Sure it is. Page 191 of the PHB. I'll read it to you: "When the trigger event occurs [his attack], you can either take your reaction right after the trigger finishes or ignore the trigger." So, you can pull the lever after I resolve his attack on you, but not before it. Sorry.
Me: Wow, that sucks.
You: Then what was the point of my standing there holding the lever???
DM: Nothing, I guess you should have just pulled it on your turn and hoped he survived. *grins*
Me: Well, don't I get to shoot him? My circumstance for attacking was if he moves at all, he must be moving to draw an arrow and shot.
DM: Huh? Oh, well... yeah, I guess so. You get to roll to attack him first.
You: Wait, wait, wait! So, he can shoot his crossbow first, then the bowman is shooting me, and then I get to pull the lever? This is so messed up...
So, unfortunately, because of the wording and despite the intent of both you and me, I would get to shoot and you get shot. I think this ruling needs some serious revamping.
"How absurd they are" as you observe is an opinion. As I have said, house rules are great. By all means make house rules and I hope you eliminate all those absurdities you are bothered by. Got a few house rules myself.
Me? Played a lot of RPGs with lotsa lotsa different init systems and "ready" rules. Each produced different problems. Each had their own absurdities.
The difference was that the frequency that ready-action-issues came up in play was always directly proportional to how much the rules favored the ready. The more they attempted to resolve the niche case the more they made the niche case a common event, not niche. You spotlight the glitch even more.
As for walking onto trapdoor vs being on trapdoor example - seems obvious to me. One he is already there - other he is moving there.
As for moving vs bowing - one set to one way one set to another - I got no rationale for bowing always wins vs moving always wins or one loses vs one wins cuz honestly there are many many imagined examples that can go either way - many other factors at play that the rules dont try to assess.
I mean, what if the mover is halted or slowed? Shouldn't that fit into the level vs mover vs bow isdues?
What if the mover is proficient in athletics vs a bow guy not proficient in bow? Shouldn't the more skilled archer have a better chance at first than novice picking up the bow for first time. (Ever played in systems where "first resolve" was determined by net successes at task? I have. Adds a whole different take an ready that makes fretting over "ready first" quite absurd to some.)
So, fussing over the degrees of absurdity between two different who goes first is like fussing the relative quality of Twinkies vs Hot Pockets.
But, taking that into the realm of general bashing with "How could these scenarios never arise in play testing and if they did, why rule it in such an ambiguous manner?" Is truly absurd.
They did occur in playtesting and they made a decision, design choice, to produce a simple and ready-is-fairly-weak rule that you find unsatisfactory. If I had to guess, at least part of that choice came from them also seeing that more powerful ready led to more cases of problems.
You want mo' ready mo' often? House rule it. Maybe you will find that silver bullet that system after system has failed.
But my guess is it wont be from a ready tweak.
Why?
**The Underlying Issue is not Ready**
The underlying issue is the initiative system.
5e uses an "actor based init" where who is doing a thing determines when it gets done and what us being done has no impact on that in most cases.
That is the underpinning of the action system.
When one frets about how you want to lever faster than bow or bow faster than lever, that is trying to turn it into an "action based init" where **what you are doing** is a lot more important than **who is doing it.**
I refer you to Unisystem variants and more than a few other systems where the resolution is determined by **action type** and "initiative" is more for declaration and decision.
In those systems the default may be that "weapon in hand" beats "move and bow" hands down, no special rule needed.
A facet of those is you tailor resolution order to fit genre... Buffy puts even quick spells last, melee before ranged iirc. Meanwhile Doctor Who resolved talking-before-running-before-sciencing-before-fighting as a matter of course. Meanwhile more scifi action resolves weapon in hand first before draw-n-fire or move-n-fire - as a matter of course.
But, guess what? That's a bit more complex than roll init and resolve in order of actor and let's not fo a lot of parsing of bow faster than dagger or spell stuff. Its was a design choice for the 5e core rules to use the simpler actor-based approach. Same approach that gave a weak-ready.
I dont like hot pockets but like twinkies, yet that doesn't drive me to think hot pockets are absurd or that the makers of hot pockets failed to taste test. Just that they went a different direct than I like. I can buy twinkies or even buy hot pockets and try and fix them up.