Readied actions triggering off of things that happen in the middle of an action

[Doctor Proctor]

A bit dramatic, eh?
Readied actions are the perfect counter for flyby attacks against my melee only fighter.

No, Pinning Smash (MP Lvl 5 Daily) is the perfect counter for flyby attacks against your melee Fighter. Of course, readying Pinning Smash for the next time the Dragon flies by would be a good way to get it to go off.

 

[AbdulAlhazred]

I think you might be being a bit harsh here. Calling a readied action that will key off of an Immediate Interrupt is a bit of a corner case, and very hard to parse out. This is what DM's are for, is to sort this kind of stuff out.

Personally, I would just call this a corner case and say that you couldn't do an Immediate Reaction directly after the Immediate Interrupt, because you're effectively allowing an Immediate Reaction ability to act as an Immediate Interrupt. In other words, treat it as if you had said "I'm going to attack as soon as that enemy tries to hit the Wizard". The enemy would make his attack, the Wizard would use Shield, the enemy would complete his attack, and then you would attack.

That sequence makes the most sense to me, and even has some RAW suport behind it (the whole keying off of enemy actions, for example), but your YMMV. I just think that allowing you to key readied actions off of Immediate Interrupt abilities just allows for too much abuse. For example, you could have your entire party ready attacks keyed off of the Wizard using Shield. When an enemy attacks the Wizard he uses Shield and then the entire party performs their actions. You could easily kill the enemy before he even completes the action that initially triggered the Shield...which hardly seems to be the designer's intention.

Actually I don't see a problem with this example at all... The whole party would have to give up its attacks for an entire round and slip its initiative down past other enemies which presumably would be acting in the meantime on the off chance that an enemy attacks the wizard and he uses shield. I doubt it would be much of a good strategy in general. It might conceivably give some advantage in some particular tactical situation but since readying is not without cost I'm good with it

This is something in general people are forgetting to take into consideration. Ready An Action isn't free. Slipping your initiative down past other enemies gives those enemies effectively an extra action vs yourself. Its not a massive cost, but there has to be a decent reason to do it before its worthwhile. Whatever action you end up taking is no better overall than any action you could normally take. Its superiority will only be in terms of the situation at that time being better than the situation in your own turn. Add in the risk of the action never triggering and its easy to see there's nothing magically great about it. Once in a while a PC will ready, probably to let them benefit from a leader buff or to hit a monster that's kiting, etc.

 

[eamon]

I agree with both Doctor Proctor and AbdulAlhazred ;-).

I don't think most Immediate Reactions make much sense if they can effectively become interrupts just by piggybacking off another interrupt - taken to an extreme, this could really become ridiculous.

On the other hand I think this isn't exactly likely to actually occur. For that matter, many other ok-by-the rules situations can result in some pretty crazy action orderings. I mean, you could conceivably construct long chains of immediate reactions that end up inserting almost arbitrarily many actions in the middle of someone's single turn. And the ordering of immediate reactions isn't really well defined.

Even a single player can stack some pretty unlikely amount of actions. A fighter adjacent to a marked creature making a ranged attack gets two melee basic attacks before the marked creature can make its attacks. Some can make it much worse. Who? "Pinball wizard", a barbarian, might make an OA and to score a critical hit - triggering his charging rampage feat and permitting him to charge someone else - and if he drops that other creature to 0, he could trigger his Swift Charge power and charge back to the creature that provoked the OA (and he hasn't even used his immediate action yet, which he could conceivably have used to introduce another charge) - "pinball wizard" would have interrupted another's movement -then hit him - then charged away, dropped someone - then charged back and hit the original target again - all before the original target can make just one more step on his path, and all without any readied action or indeed any immediate action.

That's just a consequence of the abstract nature of D&D combat. If anything, the problem isn't readied actions, it's reactions in general, and interrupts in particular.

Fortunately none of these extreme cases are likely to occur with any frequency, and generally, when they do, they won't massively disrupt gameplay.

If it turns into an abusive problem the DM can step in. But I wouldn't sweat the small stuff, it's just too common and to fix it you'd need to basically redesign 4e combat.