Opportunity attacks and cover

[Coffee_Dragon]

Say some incorporeal undead is having fun moving up to someone from total cover (through a floor or wall), attacking and moving out again. In case the creature is moving away at the same time it's moving behind cover, it incurs an opportunity attack because the movement is interrupted at a point where the creature is neither out of range nor behind cover. If it moves up, down or sideways into an adjacent square/box (even if it's only touching corners), no OA is triggered and from that point it's safe behind cover to move further if it wishes. This seems mechanically clear-cut but may raise questions about what kind of behaviour is intended to incur OAs: regardless of how far or in which direction a creature moves, it's assumed to turn and expose itself when and only when it would move outside someone's reach.

DM: "It escaped you, but you didn't get a parting shot because it was still close enough to attack."

Player: "..."

This may be one of those cases where you just have to accept the consequences of the chosen abstraction? Thoughts?

[MaxWilson]

No comment on the "incorporeal undead" scenario (honestly 5E opportunity attacks don't make much sense anyway from a fluff perspective--retreating is safer than advancing, not more dangerous).

My only comment here is that you've discovered why Mobile Moon Druids in Earth Elemental form are terrifying.

[gfishfunk]

I think its a great way to piss off your players - unless you have a scenario that is more about out-thinking the thing and treating it like a trap or a hazard.

Per RAW, you get attacks of opportunity. You just get them. If you were to create a specific monster that ignores attacks of opportunity, you can do that as well as GM. Many monsters have specific rules that adjust how they are treated in combat.

[DanyBallon]

I'd say that you get you OA, because the way I see it, what triggers the OA is moving out of range without taking precautions (disengage). In your case the creature may still be close enough, but is moving out of you range (behind cover) without being cautious, hence why I would allow OA.

[Mjolnirbear]

An attack of opportunity represents turning your back as you try to escape. If I'm fighting someone and they are moving away from me out of my reach, the most natural way to do this is turn your back to me so you can do that. You show me your back and of course I'll punish you for it.

Disengaging represents carefully backing away. Backing away is not natural and not all that easy to do unless you're certain of your footing and of the route, which is why it takes most people a whole action.

It happens during the transition of leaving my space because while you're in my space, I'm a threat: it's logical to assume you would face a threat while you're in range. You would only turn your back at the last second which is when I attack and also why I only get one AoO.

Using the ghost example using cover to avoid AoO is a metagame problem. Because an AoO represents a transition where you turn at the last moment so you can flee. We stick it at *leaving your threatened space* for simplicity. If you are ducking** behind the corner of a wall for cover, you are either carefully facing me the whole way (disengaging) or you need to check to make sure you are about to take the right path then turn at the last moment to move behind cover, thus transition, thus AoO.

I would say unless the ghost disengages, you get an AoO, because ducking behind cover is the same kind of transition as leaving my threatened space. Using the cover rules to avoid the AoO rules is metagaming.

The fact that the ghost is immaterial makes no difference. It is either unconcerned about my attack and turns its back to me as it sinks into the floor, or it is wary and facing me, so uncertain of its transition from threatened to safe which is where I get my attack of opportunity.

I'd assume that even if I get my AoO, the ghost has 3/4 cover. Because the ghost will get at least mostly underground before it tries to transition. Also because incorporeal is meant to be challenging and frustrating, and you don't need to remove AoO completely to accomplish that

** Amusingly, my autocorrect has finally realised that I never mean ducking, I mean the other word that's not allowed on the forums. This is the first I've had to change it back to 'ducking' .

[Ashaman]

Interesting discussion. Let's extend it. I've got a related scenario:
My Sorcerer has Minor Illusion cantrip. The spell description says that physical interaction reveals the illusion, or that you can see through the illusion if you use your action and do an Investigation check.
So, my Sorcerer is in melee with a goblin, and on his turn he creates a minor illusion that the stone floor flows up into a 5' tall stone wall between him and his attacker, breaking line of sight. For the next couple of seconds, I've got an illusion of full cover. Then the sorcerer just turns and walks away.
The goblin would normally be able to take an AoO using his reaction. But at this moment, the goblin still thinks the stone wall is solid, and it certainly looks solid, so he thinks he can't attack through it. He can't see what I'm doing, so he doesn't even know I'm walking away. Once his turn comes around, he can take an action to investigate, or swing at the wall to see how strong it might be, but by then I've already walked across the room.

Is this just a magical fluff to Disengage? If so, what happens in a few levels when I can quicken the Minor Illusion and then cast another attack cantrip?
Remember that being able to teleport away also prevents an AoO, seems like I've found another way to accomplish the same thing.

[MaxWilson]

Disengaging represents carefully backing away. Backing away is not natural and not all that easy to do unless you're certain of your footing and of the route, which is why it takes most people a whole action.

Surely you jest. Retreating is the easiest and most natural fencing defense there is. What is hard is attacking someone who retreats, without overcommitting and exposing yourself.

It is what it is, but 5E has retreating backwards. In GURPS retreating actually gives you a +3 to Dodge and a +1 bonus to Parry.




Is this just a magical fluff to Disengage? If so, what happens in a few levels when I can quicken the Minor Illusion and then cast another attack cantrip?
Remember that being able to teleport away also prevents an AoO, seems like I've found another way to accomplish the same thing.

By RAW you can AoO only a target that you can see, so yes, Quicked Minor Illusion will protect you from AoO in this scenario.

[KorvinStarmast]

You can treat it as AoO if the being (http://rpg.stackexchange.com/a/72666/22566) does not use the Disengage action, but I find that the rules address the whole issue better with regular creatures than with the incorporeal.

I agree with Max regarding Ashaman's question.

[Cybren]

Surely you jest. Retreating is the easiest and most natural fencing defense there is. What is hard is attacking someone who retreats, without overcommitting and exposing yourself.

It is what it is, but 5E has retreating backwards. In GURPS retreating actually gives you a +3 to Dodge and a +1 bonus to Parry.



By RAW you can AoO only a target that you can see, so yes, Quicked Minor Illusion will protect you from AoO in this scenario.

Opportunity attacks are a cludge to address the 6 second combat round. GURPS has one second turns, it can be distinct and explicit. In 3.x, there were so many AoOs to represent spending time in your turn doing something other than specifically defending yourself in melee. The 5 foot step was important in representing cautious retreating of ground. 4e had the shift. 5e has that as disengage now, in line with the simplification of things. Which I think is fair, as a general rule, unless you're Chuck Liddel, it's incredibly difficult to attack in a mea girl way [i]during[/] your retreat and not immediately before or after it.

[JackPhoenix]

Surely you jest. Retreating is the easiest and most natural fencing defense there is. What is hard is attacking someone who retreats, without overcommitting and exposing yourself.

It is what it is, but 5E has retreating backwards. In GURPS retreating actually gives you a +3 to Dodge and a +1 bonus to Parry.

Except the retreating you describe is the Disengage action, if you don't take that, you're not backing off, you're literally turning your back to your enemy and walking away. The enemy doesn't risk overcommitting and exposing himself when you ignore him and open yourself up for an attack with a move no-one would be stupid enough to do in real life (or at least not stupid enough to do more then once).

[Coffee_Dragon]

Bat-apologies for abandoning my own thread: I suffered a hard drive failure and sort of lost sight of it afterwards. (In case anyone was wondering, losing a hard drive sucks even when you have backups of your important stuff.)

The way this happened in our game, the undead (I guess wraiths?) appeared as bonus shenanigans at the tail end of a fight that had gone unexpectedly easily, so no one thought of it as a cheap gotcha or raised objections (although it later puzzled me enough that I took a hard look at the rules). We dealt with it by readying actions to attack when the wraiths showed up on their turns, which worked well enough.

I find it interesting that so many (here and in the linked thread) seem ready to split the reach concept into "range" and "reachability", something I can't find any concrete basis for in the rules (reach is overall poorly defined). In my view such a distinction must be regarded as a custom extension of the rules. While it does "solve" the apparent inconsistency of sidestepping behind cover, it creates an equally mystifying corner case when sidestepping behind cover without any intention of then also leaving range:

Player: "Keeping my guard up, I step behind the fence where it will be harder for him to attack me!"

DM: "But he gets a bonus swing at you, since you're moving to where it's too hard for him to attack."

Player: "..."


It happens during the transition of leaving my space because while you're in my space, I'm a threat: it's logical to assume you would face a threat while you're in range. You would only turn your back at the last second which is when I attack and also why I only get one AoO.

But that's not really a good explanation for OAs generally. You can run circles around me while keeping yourself turned towards me at all times, but if and only if you would step away from my immediate vicinity do you have to turn around instead of keep doing whatever you were doing before? I would rather have no fluff justification than one that makes me imagine people behaving bizarrely.


Using the cover rules to avoid the AoO rules is metagaming.

Ideally a tactical system should have robust rules that render the question of metagaming irrelevant: players should be expected to favour actions that are advantageous to them in the system, to reflect the will and ability of in-game actors to perform actions that are advantageous to them in the fiction.


The fact that the ghost is immaterial makes no difference. It is either unconcerned about my attack and turns its back to me as it sinks into the floor, or it is wary and facing me, so uncertain of its transition from threatened to safe which is where I get my attack of opportunity.

I'm not sure I follow this. The immateriality of the ghost (wraith, etc.) is what allows it to move into a protected space while maintaining the exact same stance/behaviour that normally allows anyone to not incur an extra attack when moving into an open space. Why should the fact that the ghost has total mobility in the destination space and I have none make it more susceptible to attack?


I'd assume that even if I get my AoO, the ghost has 3/4 cover. Because the ghost will get at least mostly underground before it tries to transition.

By the rules it would get no cover if you were entitled to an attack, since your OA interrupts its movement while it's still in an open square, and there's no such thing as "between squares" (although it's easy enough for the DM to override).

[MaxWilson]

But that's not really a good explanation for OAs generally. You can run circles around me while keeping yourself turned towards me at all times, but if and only if you would step away from my immediate vicinity do you have to turn around instead of keep doing whatever you were doing before? I would rather have no fluff justification than one that makes me imagine people behaving bizarrely.

OAs in 5E make no sense.

If you want a rule that makes physical sense, try this:

(1) There is no "Disengage" action.
(2) Turning your back on someone gives them an OA against you.
(3) You can move backwards at half speed. Your speed is halved for the entire round.

Ta-da! What was formerly accomplished with "Disengage" is now accomplished by Dashing backwards, but you can also choose to back off, accept the speed penalty, and engage another target within your now-reduced movement range.

This is pretty much how AD&D worked, except you also got a +4 to hit someone turning their back on you, which could be modeled in 5E by granting advantage on the OA.

[Coffee_Dragon]

If you want a rule that makes physical sense, try this:

(1) There is no "Disengage" action.
(2) Turning your back on someone gives them an OA against you.
(3) You can move backwards at half speed. Your speed is halved for the entire round.

Actually I was thinking exactly that if a DM insisted on an "OA represents turning your back" interpretation, I'd ask to move backwards at half speed. If Disengage means moving away without turning, it should give you some movement.

Main reason for bumping is I noticed these tweets from Jeremy C.:


Q: Does an earth elemental trigger an OA when it burrows? It is within 5 ft, but the creature can no longer reach it

A: An opportunity attack occurs right before the target leaves your reach (PH, 195).

Q: thanks. yes, the debate here was does it ever leave your reach if it goes into the ground adjacent to you

A: Your melee reach does not extend into the wall or floor.

What's funny about this is that as far as I can tell, he's effectively making this rule up: I could find no place in the rules where reach is defined or even implied to work like this. Also I guess "free attack because someone was suddenly too well protected against attack" is now a thing.

[EvilestWeevil]

I have been in this scenario with a DM before in 3.5, and of the couple times he did this to the group, all I can remember is that I was really really bored. It's just super boring having to ready an attack to hit a thing that can pop out of nowhere, its frustrating and simply not fun. So beware DM's that use this tactic, that when your players are on their phone, you truly and assuredly know why.

[BurgerBeast]

OAs in 5E make no sense.

If you want a rule that makes physical sense, try this:

(1) There is no "Disengage" action.
(2) Turning your back on someone gives them an OA against you.
(3) You can move backwards at half speed. Your speed is halved for the entire round.

Ta-da!...

Unless I'm missing something, this is a perfect fix. It accomplishes everything that I think the developers created the Disengage action to accomplish, but is more elegant and more useful. It makes perfect sense, and on top of that, if it were the default rule, it would've solved this thread before it arose.

[bid]

Unless I'm missing something, this is a perfect fix. It accomplishes everything that I think the developers created the Disengage action to accomplish, but is more elegant and more useful. It makes perfect sense, and on top of that, if it were the default rule, it would've solved this thread before it arose.
Except it breaks the action economy. You can move 15' and attack anything.

[RickAllison]

Except it breaks the action economy. You can move 15' and attack anything.

Indeed. Devalues Mobile, Swashbuckler, and especially the Rogue.

[coredump]

Except the retreating you describe is the Disengage action, if you don't take that, you're not backing off, you're literally turning your back to your enemy and walking away.
I don't see anything in the rules that supports this. Nor does it make sense, no one is going to just turn around like that.



OAs in 5E make no sense.

If you want a rule that makes physical sense, try this:

(1) There is no "Disengage" action.
(2) Turning your back on someone gives them an OA against you.
(3) You can move backwards at half speed. Your speed is halved for the entire round.
Basically, Disengage goes from 'costing' an action to 'costing' half of your movement.
It makes sense, but I don't think it accomplishes what the game designers are after from a game design perspective. I think the real problem is that you can leave without being followed... and that isn't realistic. IMO the OA rules are to compensate for that more than anything.




Ta-da! What was formerly accomplished with "Disengage" is now accomplished by Dashing backwards, but you can also choose to back off, accept the speed penalty, and engage another target within your now-reduced movement range.

This is pretty much how AD&D worked, except you also got a +4 to hit someone turning their back on you, which could be modeled in 5E by granting advantage on the OA.[/QUOTE]

[RickAllison]

I'll put out my little blurb on how I feel about Disengage and OAs. To me, OAs are not turning your back to the opponent, but losing leverage. You put yourself in a position where you can neither threaten your opponent due to being off-step, nor put up as effective a guard as normal. Devoting an action/bonus action to Disengaging is sacrificing movement because you are being cognizant of the combatants around you, going slower because you are keeping everyone in your peripheral vision.

Mobile and Swashbuckler play off this by learning to strike, then taking advantage of the defender's attempt to deflect it by moving. Cunning Action plays off of feints, accomplishing the same purpose as SB/Mobile without getting to commit as much. Step of the Wind lets the monk focus on maximum speed, or making quick steps that prevent him from being caught off-guard. The Sentinel learns to not be fooled by the feints of the rogue and catches the monk between steps to prevent escape.

Just my two coppers.

[BurgerBeast]

Except it breaks the action economy. You can move 15' and attack anything.

I don't see the connection to breaking the action economy. If everyone has the ability to do it, the economy doesn't break.


Indeed. Devalues Mobile, Swashbuckler, and especially the Rogue.

This is a good point. They still have value, but it is rather seriously reduced. But the half-speed is pretty arbitrary and can be changed. Alternatively, if the designers had come up with the half speed to go backward rule, they likely would've just made the mentioned qualities work in different ways to ensure a good enough benefit.


Basically, Disengage goes from 'costing' an action to 'costing' half of your movement.
It makes sense, but I don't think it accomplishes what the game designers are after from a game design perspective. I think the real problem is that you can leave without being followed... and that isn't realistic. IMO the OA rules are to compensate for that more than anything.

Yeah, so I am operating on the assumption that the reason why leaving threat ranges draws AoOs is that it prevents people from running out of combat. In 5e, this means you could dash for double movement, but not if without a cost if you're engaged. Then you can either disengage w/o an AoO or you can dash but draw an AoO.

This, to me, essentially reflects the spirit of not being able to "turn your back," albeit not necessarily literally. If you want to cover double the ground, you can't devote adequate attention to your defences to benefit from a disengage.

I'm a bit lost on the idea that there is a built in method to prevent characters from moving without being followed. The turn-based nature of combat means that you can essentially (with the exception of feats designed to prevent it) always move without being followed.

[Citan]

An attack of opportunity represents turning your back as you try to escape. If I'm fighting someone and they are moving away from me out of my reach, the most natural way to do this is turn your back to me so you can do that. You show me your back and of course I'll punish you for it.

Disengaging represents carefully backing away. Backing away is not natural and not all that easy to do unless you're certain of your footing and of the route, which is why it takes most people a whole action.
WUT????

Did you never have a fight, even a friendly one?

You turn your back on an enemy ONLY when you RUN away (which should be translated as Dashing in D&d).
Otherwise, "never turn your back on an enemy" is the first and golden rule everyone learns as their first lesson, for obvious reasons.

Imo, opportunity attacks feel a bit unrealistic in D&d because they are too systematic. Although it's coherent with the whole "simplicity" paradigm of 5e.
If they had focused on more fine-grained rules, they could have probably distinguised different cases.

But that's probably why they created Disengage as an action, simulating the fact that you first take a few reverse steps while staying on guard, eyes on enemies, then you turn around and continue moving normally once you're out of his reach. And balanced the cost by using the reaction.
My only gripe with the system as-is it that they made Disengage an action and not a bonus action, ubt it's because I personnally feel strange that a character that can strike several times, cast a powerful spell or run its usual distance in 6 seconds would, at the same time, be clunky enough to take 6 sec just to reverse walk 5-10 feet.
And while your point is certainly valid in real life, for normal people, it feels awkward in an universe where every PC is capable of everything I told just above, and where everyone is focused enough to even know when someone is attacking them in the back. So memorizing the terrain around should not be hard for such perceptive people. :)

But well, at least it makes a defining feature for Rogues (and Monks). :)

[Mellack]

I think disengage takes an action because of (1) action economy and (2) the game construct of turns. Because of turns each character moves separately, so it is easy to walk away and leave somebody's attack reach. In reality, if you just move slowly backward the attacker will move forward immediately after you. If you want to actually get away from them you need to move quickly (run) or do some fancy movement to evade them (disengage). I think just imagining them slowly backing away while the attacker stands still and watches to be quite odd.

[Vogonjeltz]

Say some incorporeal undead is having fun moving up to someone from total cover (through a floor or wall), attacking and moving out again. In case the creature is moving away at the same time it's moving behind cover, it incurs an opportunity attack because the movement is interrupted at a point where the creature is neither out of range nor behind cover.

I'd say no opportunity attack is possible in that situation; it's a clever use of incorporeality and cover.