D&D 5E Opportunity Attack around a Corner: Yes or No?

[FitzTheRuke]

BTW, Grimmwald and Kalista are in deep trouble with these orcs.

 

[ECMO3]

Rules question for you folks. This is something my players and I have butted heads on, and I want to know if I'm in the minority on this (and if I am, then I'm prepared to adjust gracefully).

In the picture below, if the orc takes the path marked in blue, does Grimmwald get an opportunity attack when the orc leaves the square with the dot in it? I think it's cheesy as all get-out, but my players think it should be allowed.

View attachment 136193

The PHB says this (p. 192): Corners. Diagonal movement can’t cross the corner of a wall, large tree, or other terrain feature that fills its space.

But in this case, "crossing the corner of a wall" is debatable. It could be argued that Grimmwald wouldn't actually be crossing the corner. Personally, I think the intent was to rule out this situation, but it's not unambiguous.

How would you handle this at your table?

Short answer yes. However RAW you can move through an allies space (as difficult terrain). Assuming he is going to stop where the blue line ends he should move diagonal (norwest) into the other orcs's space and then move north to be next to Kalista. Another option is to just move north from the blue dot area and then he never leaves Grimwalds reach (although he is flanked if you use those rules).

 

[Hriston]

I'm not convinced that going along the grid line counts as an obstacle in a way the rules contemplate.

Agreed. Touching or traveling along the wall doesn’t count as being blocked by the wall, so there’s no cover.

 

[jayoungr]

First off, the image I posted is a mock-up to show the issue. In the actual game, there were more PCs around.

Second, thinking about it further, I think what bothers me here is the line of sight. It doesn't seem like Grimmwald should be able to see around the corner well enough to make the split-second reaction needed for an opportunity attack.

 

[humble minion]

First off, the image I posted is a mock-up to show the issue. In the actual game, there were more PCs around.

Second, thinking about it further, I think what bothers me here is the line of sight. It doesn't seem like Grimmwald should be able to see around the corner well enough to make the split-second reaction needed for an opportunity attack.

Hmm, so if the orc had started its turn in the square with the dot, in line of sight of Grimmwald, and then moved away to its destination, would you have allowed the attack of opportunity?

 

[DEFCON 1]

Yes, he gets to make an OA, and the orc gets +2 to AC.

But I also agree with the poster above about the orc just moving into the ally's space before moving up to K, thereby removing the worry of the question altogether.

 

[Oofta]

We never apply cover penalty for melee attacks (or ranged attacks if the attacker is adjacent to the corner) around a corner in our games, but it doesn't change anything.

Unless the target cannot be seen, leaving an adjacent space provokes an attack of opportunity. As the rules state:

You can make an opportunity attack when a hostile creature that you can see moves out of your reach.​

​

Does Grimmwald have reach to the adjacent square? Yes. Does the orc move out of that square? Yes. Is that square under total cover, totally concealed, or is there some other reason the orc could not be seen? No. Therefore Grimmwald gets an opportunity attack. Debates about cover are irrelevant.

 

[Lycurgon]

The corner rule only applies to Movement. RAW is clear. I believe the Spirit of the rules it only applies to movement. If they had intended for the "not moving through hard corners" rule to apply to other things like AOO then they would have said so. They are very clear on what provokes AOOs, and corners don't factor in at all. So my conclusion is RAI, hard corner rules only apply to movement.

 

[Shadowdweller00]

If you're having difficulties conceptualizing why Grimmwald could attack around the corner, I would tend to say: Don't straightjacket your thinking into a presumption that characters and movement ONLY occur in nice, discrete squares. Consider a case where Grimmwald is leaning half his body around the corner, possibly using it for cover. Or...any diagonal movement really - do you presume that creatures moving diagonally thread themselves through an impossibly thin square corner without passing through the adjacent two squares? It's helpful to reduce movement to squares in combat a lot of the time.

...but you shouldn't, you know, let it keep you from envisioning and utilizing situations such as where a lone guard tries (operative word - tries) to stay in the exact middle of a 10 foot / two square wide hall to block interlopers from getting past.

 

[TwoSix]

I think the fiction here is highly relevant. Is Grimmwald hiding behind the corner, waiting to ambush the orcs? Or did he run forward and just make it to this spot before his movement ran out?

I generally treat positioning on the grid as somewhat probabilistic, the square is "about" the character's position, but they probably move around a fair amount during the 6 seconds. Using walls and corners is also generally something I want to encourage, since it encourages more dynamic movement during the fight, so I almost always give at least a half-cover bonus for attacks that might be in any way encumbered by local terrain.