FormerlyHemlock
Hero
Ok, thanks for the answers and the additional example. I have some more questions, though. Here is one part of the combat encounter that I referred to earlier.
Scenario A:
- Three goblins are standing together
- Bard PC is about 30 ft. away from them
- Paladin PC is about 15 ft. away from them
- The goblins’ declared action is that they are going to scatter looking for cover and then shoot at the paladin.
My concern for the moment will be the bard’s declared action. When we ran this with cyclic initiative, the bard got to go before the goblins. He ran right up into the goblins’ face and cast Thunderwave. (Not that is matters, but the bard rolled well and the goblins didn’t. This was cool because dead flying goblins.) So my first question is, (A1) with simultaneous initiative ala Hemlock would that even have a chance of working? My analysis: If I “strictly enforce” Everything Happens at Once ™, then it would seem to me that the answer is no – the goblins would scatter while the bard was approaching, so this isn’t even worth trying. OTOH, since initiative contests are possible, then perhaps this should be treated as one.
I'll stop you right here for a second just to say yes, this is exactly how I would run it. If the Bard is trying to run up and send goblins flying, then he does so to every goblin who doesn't beat his initiative. (Or if they all beat his initiative, then he aborts his action and doesn't use a spell slot because he was too slow.)
However, this would then bring up two more questions. (A2) If there is an initiative contest, does this result in the winner getting to take his entire turn (e.g., bard’s move and cast) before the loser gets to do anything or is the contest somehow at a finer granularity?
In principle you could try to do it at a finer level of granularity, but I wouldn't for a TTRPG. I have a computerized project I'm working on in which I was just considering earlier today what kinds of initiative systems I might want to provide as options, and in addition to regular PHB turn-by-turn cyclic initiative and declare/act "simultaneous" initiative, it might be fun to factor movement speed in somehow in just the way you suggest, so that when you watch the battle it appears to be basically in realtime. But I haven't done so in my computerized project, and I wouldn't even consider doing so in actual table play without computers.
Of course there's also a whole middle ground wherein the DM could just make an ad hoc ruling which results in something reasonable, e.g. "okay bard, you can try it but you'll have disadvantage on your initiative roll because you have to run so far so quickly while prepping your Thunderwave." Use your judgment as DM.
(A3) How much of the bard’s action declaration can be contingent on the initiative result? (E.g., Do I allow, “If the goblins stay still, I run up to them and cast Thunderwave, but if the goblins scatter before I can move, then I stay where I am and shoot at the bugbear in front of the paladin.”, or does it have to be more like, “I run toward the goblins (unconditionally). If I get to them before they scatter, then I cast Thunderwave, otherwise I turn and shoot at the bugbear in front of the paladin.”?) Or if there is some other way that this should go that I am not seeing, just ignore the questions and describe that instead.
I allow moderately complex declarations. There's probably a point at which I would say, "No way, that's too complicated," but I don't know what it is because no one has ever tried to do so. Of the options you listed, all of them seem reasonable to me and I'd allow any.
Since I'm using rounds to basically represent OODA loops, I basically figure that any intention the player can state in a couple of sentences is probably one that a combatant can form as a discrete intention (the "decision" part of OODA) so I'm inclined to be generous. I think it's totally reasonable that a bard would be able to see whether the goblins are responding quickly enough for him to blast them with Thunderwave before they can scatter--humans aren't that good at judging relative accelerations but we're decent at judging relative velocities and distances.
Scenario B: (only interesting if the answer to A1 is “no”)
For me, A1 is "yes".

How about for you? How would you rule?