
Thaboe |

So I got into a little spat with one of my players regarding climbing up a 15 ft wall. So He has 30 ft movement and takes a -5 for fast climbing and gets a 22 on a DC 15 wall. So he climbs up 15 ft. Pretty straight forward.
I ask for a second check to pull himself up and move. He argues he has cleared the wall because he has "climbed 15 ft". He considers himself as occupying the first vertical square and starts moving from there (top of his hands) and i consider him occupying the ground and needing to move up the first 5 ft of the wall (starting from the feet).
What is the correct reasoning?
I hope this doesn't become as lengthy as the 'distanced jumped' discussion...

Chemlak |
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1) Expect people to disagree.
2) I agree with your player.
Pathfinder doesn't do 3D very well, and I tend to just use the 2D rules shifted through 90 degrees, which means that the cube the PC is standing in has 10' of wall to move over, and the last 5' represents cresting the wall.

Bob Bob Bob |
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I agree with both things Chemlak said. Basically, I've always translated "square" (as in, you occupy a 5 foot square) to "cube" any time anything 3-D became necessary. I know it's an abstraction (I think most medium characters are actually taller than 5 feet) but it's basically the simplest (and easiest) way to translate the wargaming map it still seems to think people use to a 3-D structure. Under that kind of translation the player is already 5 feet up the wall (since their cube is 5 feet tall).
Real question, how far do you think a player has to climb to climb a 5-foot wall? Do they need 10 feet of movement to do it (5 feet to climb the wall, 5 feet to pull themself up)? Because that sounds a little silly. They can literally reach the top of the wall. The effort is just pulling themself up.

Gauss |
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So I got into a little spat with one of my players regarding climbing up a 15 ft wall. So He has 30 ft movement and takes a -5 for fast climbing and gets a 22 on a DC 15 wall. So he climbs up 15 ft. Pretty straight forward.
I ask for a second check to pull himself up and move. He argues he has cleared the wall because he has "climbed 15 ft". He considers himself as occupying the first vertical square and starts moving from there (top of his hands) and i consider him occupying the ground and needing to move up the first 5 ft of the wall (starting from the feet).
What is the correct reasoning?
I hope this doesn't become as lengthy as the 'distanced jumped' discussion...
It doesn't matter if you are measuring from square to square, feet to feet, top of head to top of head, 15feet is still 15feet.
XP
3
2
1P
(1 = 5', 2 = 10', 3 = 15', X = open space above the wall, P = player character)
IF you measure from 1P to XP it is 3 squares (each being 5' for a total of 15').
If you measure from the bottom of 1P to the bottom of XP it is still 15'.
If you measure from the top of 1P to the top of XP it is still 15'.
I think your problem is that you are changing the measuring point.
My guess is that you are measuring movement as 'from the feet' but measuring the distance required as 'from the top of the character' which means that in your mind there was 15' of wall ABOVE the character for a total wall height of 20'.

Komoda |

It would be measured from feet to feet or hand to hand. It doesn't matter which, it is the same distance.
The only real reason the jump argument was a thing is because the jump DC conflicts with itself in the same paragraph. Climb does not have that problem.
If you measure from feet to feet, and start on the ground, and climb 15', your feet are 15' off of the ground. If the wall is 15', you are on top of it.
If you measure from hand to hand, and start from 5' off the ground (a conservative and easy number to work with assuming reaching straight out and grabbing the wall) and climb 15' your hands are 20' off of the ground. If the wall is 15' tall, you would be on top of the wall.

![]() |
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The only real reason the jump argument was a thing is because the jump DC conflicts with itself in the same paragraph. Climb does not have that problem.
^ this.
With Acrobatics, the DC is tied in with the distance traveled.
With Climb, the DC is simply a target to meet, and then you move.
If it helps, draw a side profile of the wall, treating the character as occupying a 5-foot cube. The character actually occupies the bottom five feet of that fifteen foot wall.
Therefore, climbing 15 feet puts them on top.
X
[]
[]
[]Y
X = End of movement.
Y = Beginning position.

Forseti |
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None of the reasoning actually matters. No need to overthink it. The whole thing is an abstraction anyway so why bother with minutiae not mentioned in the rules? Want to get on top of a 15' wall? Climb 15'. Want to jump over a 15' pit? Jump 15'. Complicating it beyond that leads to nothing constructive.

Komoda |

None of the reasoning actually matters. No need to overthink it. The whole thing is an abstraction anyway so why bother with minutiae not mentioned in the rules? Want to get on top of a 15' wall? Climb 15'. Want to jump over a 15' pit? Jump 15'. Complicating it beyond that leads to nothing constructive.
Over complicating it isn't the issue. Jumping 15' to jump over a 15' pit means you jump into the pit. You need to move more than 15' to do it. If the pit takes up 3 squares, you need to move into the forth, meaning your character moves 20 ft. There is a level of complication to this game that is important.

Bill Dunn |
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There is a level of complication to this game that is important.
No, it isn't. Your jump check is 15 and the DC is 15? You succeed!
The wall is 15 feet high and you climbed 15 feet? You're on top of the wall!The grid's just an abstraction to make things easier and more convenient than carrying around a tape measure, not more complicated.

GinoA |
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Over complicating it isn't the issue. Jumping 15' to jump over a 15' pit means you jump into the pit. You need to move more than 15' to do it. If the pit takes up 3 squares, you need to move into the forth, meaning your character moves 20 ft. There is a level of complication to this game that is important.
Irrelevant. The DC to jump a 15' pit is 15. If you want to understand that as 20' spent airborne, knock yourself out. That means that jumping from one square to an adjacent square (5' airborne) has a DC of 0. Everything still works fine.

Komoda |

Komoda wrote:Over complicating it isn't the issue. Jumping 15' to jump over a 15' pit means you jump into the pit. You need to move more than 15' to do it. If the pit takes up 3 squares, you need to move into the forth, meaning your character moves 20 ft. There is a level of complication to this game that is important.Irrelevant. The DC to jump a 15' pit is 15. If you want to understand that as 20' spent airborne, knock yourself out. That means that jumping from one square to an adjacent square (5' airborne) has a DC of 0. Everything still works fine.
I wasn't talking about how far you have to jump, just that you have to move into the 4th square for a total of 20' of movement. Forseti implied that would not be the case. This has nothing to do with changing the DC from 15. And again, I specifically pointed out that my example is with the 15' pit being completely within three squares.
Bill Dunn, the grid is just as much a part of the rules as any other. It is as much an abstraction as an attack roll is. Feel free to relax its use in your game, but you shouldn't imply that someone that does stick to it is playing incorrectly.

Bill Dunn |
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Bill Dunn, the grid is just as much a part of the rules as any other. It is as much an abstraction as an attack roll is. Feel free to relax its use in your game, but you shouldn't imply that someone that does stick to it is playing incorrectly.
It's not a question of using or not using the grid. It's a question of letting it complicate the hell out of the game like using it to derange the jump rules.

Thaboe |

Real question, how far do you think a player has to climb to climb a 5-foot wall? Do they need 10 feet of movement to do it (5 feet to climb the wall, 5 feet to pull themself up)? Because that sounds a little silly. They can literally reach the top of the wall. The effort is just pulling themself up.
Well first of all, you can just 'pull yourself up the wall. (dc 15 climb) He doesn't actually need to climb distance imo. Or i have to consider pulling yourself up as though it's going at climb speed. Which opens up the conundrum of a series of chest high ledges...
But reading back, I appear to have mislead most of you with my description. The wall is adjacent to a platform and he was arguing that he moved into the platform with his climb check. Which i would consider 5 feet of extra movement in addition to the 15 feet he climbed. So as i agree, his feet were at the top for the wall or his hands were over the wall, but I still considered him climbing the wall because i hadn't considered him to actually moved onto the platform. Since a I considered the ledge a hard corner that he couldn't diagonally move through.
(Occupying the first square, climbin up from feet and 'stepping' onto the walls square.)
4 3
[]2
[]1
[]X
or is it more like
(Hands and climbing on top of the obstacle as part of the movement climb check)
3
[]2
[]1
[]X
Because what my mind turned it into was...
(distance traveled from the feet and then DC 15 to climb onto the obstacles square)
4
[]3
[]2
[]1
In which 4 is the putting him onto the platform (or 5 ft deep wall)
sorry for the confusion in my OP.

Thaboe |

The reason i'm interested in the answer this time is to figure out whether you provoke from an opponent with reach that is standing 5ft from the edge. If the opponent was standing on the edge (position 3), obviously he'd threaten and you'd provoke moving onto the obstacle (into 3).
But from reach, a hard corner ledge would provide cover if you moved directly from 1 to 3 (climbing 10 ft) and not provoking from reach. But that would mean that you have to move through a hard corner as part of your movement.
If you CAN'T move through this hard corner as part of the climb check, you have to move 1,2,3 (15 ft) and provoke from reach as you move from 2 to 3. If so, does that movement from 2 to 3 require a climb check (my original idea was that it did, but i can just as easily see that it's just regular movement, perhaps something you can 5 ft step is someone does the climbing for you (drag, reposition).
E 3 2
..[]1
..[]P
Or do hard corners only exist in 2D? That would make this a whole lot easier and allow you to move from 1 to 3 in one go, provoke an attack while doing so. And also not benefit from cover while hanging from the edge (burst effects, ranged attacks).
I know some people who like to climb along walls and i'd find it weird that the corners function differently is you approach them from the group or from the wall.

John Murdock |
The reason i'm interested in the answer this time is to figure out whether you provoke from an opponent with reach that is standing 5ft from the edge. If the opponent was standing on the edge (position 3), obviously he'd threaten and you'd provoke moving onto the obstacle (into 3).
But from reach, a hard corner ledge would provide cover if you moved directly from 1 to 3 (climbing 10 ft) and not provoking from reach. But that would mean that you have to move through a hard corner as part of your movement.
If you CAN'T move through this hard corner as part of the climb check, you have to move 1,2,3 (15 ft) and provoke from reach as you move from 2 to 3. If so, does that movement from 2 to 3 require a climb check (my original idea was that it did, but i can just as easily see that it's just regular movement, perhaps something you can 5 ft step is someone does the climbing for you (drag, reposition).
E 3 2
..[]1
..[]POr do hard corners only exist in 2D? That would make this a whole lot easier and allow you to move from 1 to 3 in one go, provoke an attack while doing so. And also not benefit from cover while hanging from the edge (burst effects, ranged attacks).
I know some people who like to climb along walls and i'd find it weird that the corners function differently is you approach them from the group or from the wall.
the reason reach weapon can AoO even if there is a corner is that reach weapon are treated as ranged weapon when calculating where the attack come from for cover, so it take its most favourable corner to see if the corner stop the attack, if the attack do not pass through a corner then you have no cover

Rub-Eta |
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So I got into a little spat with one of my players regarding climbing up a 15 ft wall. So he climbs up 15 ft. Pretty straight forward.
Seems to me like he already climbed up the wall.
vhok wrote:I would refer to the jumping 10foot hole faq in regards to this. similar thing just going up instead.The two are nothing alike, as has already been explained a few times.
Please do so again ;)

John Mechalas |
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and yet the 10foot jump rule shows you where paizo stands when it comes to measuring distance. claim they are nothing alike all you want but its very clear
They are nothing alike.
Unlike jumping a pit, you can occupy the intermediate squares when climbing a wall because you don't fall sideways. Your starting point is also the first square of the wall, not the square adjacent to it (as is the case for jumping a pit).
Jumping a 15' pit:
A --> B
[]XXX[]
[]= solid ground (5')
X= empty space (5')
Climbing a 15' wall:
B
[]
[]
[]A
[][][][][]
Count the squares moved to get from A to B. The pit requires 20' of movement (4 squares, 3 of which are the DC15 jump to clear 15' of pit).
Climbing the wall takes 15' of movement (3 squares), the last of which is diagonal.
If the player already had a diagonal move before starting this climb, then that final diagonal would count as 10'. That may make it too far for them to move in the current turn, depending on how much move they have left.

John Mechalas |
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E 3 2
[][] 1
[][] PI know some people who like to climb along walls and i'd find it weird that the corners function differently is you approach them from the group or from the wall.
In your drawing, you must go directly from 1 to 3 because position 2 is not a legal position (unless you have Air Walk or Fly). At 2, there is no wall adjacent to you, and there is no ground beneath you. It is not possible to "climb" into that square/cube.

Thaboe |

Count the squares moved to get from A to B. The pit requires 20' of movement (4 squares, 3 of which are the jump). The wall takes 15', the last of which is diagonal.If the player already had a diagonal move before starting this climb, then that final diagonal would count as 10'. That may make it too far for them to move in the current turn, depending on how much move they have left.
So then the the edge of the climb isn't treated as a hard corner? Since you move through it diagonally. Does that also mean that if I was walking perpendicular on the wall (Eg:spider climb)I could 5f step around the corners of corridors since I'm technically 'climbing the wall'?
But either way, it would still provide cover from the reach weapon to make it not provoke. Since you can only target the exposed 4 corners of his 'cube' from the closest 2 corners of your 'cube'.
(yea i know pathfinder doesn't use 3d cubes, but this happens in 3d space).

Thaboe |

Our posts crossed in the night. It can't be a hard corner because it's not legal to be hanging 5' off the edge like that. There's no wall next to you, and no ground beneath you.
How is it not legal? You saying i can't shimmy along a ledge (climbing horizontally), or take take cover from an explosion by hanging over the a railing or ledge?

John Mechalas |
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How is it not legal? You saying i can't shimmy along a ledge (climbing horizontally), or take take cover from an explosion by hanging over the a railing or ledge?
You're not on the ledge in position 2. You're in mid-air.
.. 3 2 <-- mid air
[][] 1
[][] P
[][][][][]
A closeup look at posiiton 2:
[_][_][_]
[_][2][_]
[#][_][_]
[#] = wall
[_] = Empty space
What are you standing on? Holding on to?
Edited to add: If you want there to be a ledge that sticks out far enough to support a creature at position 2, then you are creating an overhang which is a DC30 climb check.

Thaboe |

I'm sorry, i misunderstood you, i thought you were referring to position 1. Because 2 isn't a legal space when you want to put your feet on it.
But i found it strange that you'd treat a 90 degree corner as anything but a hard corner, especially when it comes to 5ft stepping when you have a climb speed, which if it isn't a hard corner, means you could to that.
As for how you could occupy the space treating it as a hard corner), you are holding on the the edge as maneuver the rest of your body up on top of the obstacle(moving to position 3). That would mean that in position 2 you'd still be climbing, but not have any cover of hiding behind the edge. You'd be holding onto the top of the wall with your hands and the side with your.
Hence you could poke someone climbing over your wall if you were wielding a long spear. And you can push someone clear off the wall (not allowing them a chance to grab it mid fall, or negating slowfall. By readying something like a bullrush.
But this was because I could not picture a 90 degree corner as anything but a hard corner.

toastedamphibian |
I would suggest not drawing your "squares" in such a way that it causes "clipping" issues.
Say the "wall" is in both squares. He climbs to the top, he is now balanced on the very edge of the wall. If he provokes an aoo leaving that square, or gets hit by a readied action, treat him as balancing(Flatfooted, needs to make a DC 5 acrobatics check or fall if injured. Climb check to catch yourself = Wall Climb Dc +20)

John Mechalas |

I would suggest not drawing your "squares" in such a way that it causes "clipping" issues.
PF uses a grid-based approach for simplicity. How you choose to resolve walls that don't fall perfectly at grid intersections is up to you, but any answer other than "round to the nearest intersection" creates inconsistencies in how the corner at the top gets handled (what's your minimum legal depth, sometimes position 2 is legal and sometimes it's not, and so on).
That's fine, as long as all players are aware of your rules for dealing with it.

toastedamphibian |
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In this case, I would say your focusing too much on the abstraction. Your losing the simplicity it is supposed to be in service of while creating results that make little sense narratively. (You cannot climb that wall, its 3 inches into the adjacent grid space...)
If I understand it, your method is that the character must pass through the corner to avoid W. Coyote imitation. Why? Just say the are 15ft higher from the cube they started in, and are on tbe cliff edge. Easy and consistent.

Thaboe |

I would suggest not drawing your "squares" in such a way that it causes "clipping" issues.
Say the "wall" is in both squares. He climbs to the top, he is now balanced on the very edge of the wall. If he provokes an aoo leaving that square, or gets hit by a readied action, treat him as balancing(Flatfooted, needs to make a DC 5 acrobatics check or fall if injured. Climb check to catch yourself = Wall Climb Dc +20)
So you mean every drop is to cover 50% of the square so you can argue you can be both standing on the square as well as climbing it?
That would be Elegant. No discussion about hard corners and provoking. You just climb through the square and provoke.But then that still doesn't resolve my issue with the 5ft stepping with a climb speed.

John Mechalas |

In this case, I would say your focusing too much on the abstraction. Your losing the simplicity it is supposed to be in service of while creating results that make little sense narratively. (You cannot climb that wall, its 3 inches into the adjacent grid space...)
This is the point of "round to the nearest grid intersection". The problem you describe doesn't really exist in that context.

Thaboe |

5ft step into John's Position 2, describe it as being on the edge of the cliff. Next turn 5ft step in. But your going to be flat-footed until you take that second step, probably not a great plan.
Or am I misunderstanding the question?
You did, according to john there is no position 2 if it's at the edge of the cliff. To avoid "W.C. syndrome.
So you'd have to 5ft step up diagonally, from his 1 to 3. Which is where my hard corner comes in.

2bz2p |

To avoid this issue with your players in the future make sure no (non-spell) walls or obstacles are in 5' increments. If that wall had been 14' or 16', you wouldn't need to argue over what 15' means.
Me - I would give it to the player without a worry. If you really can't let go of that last inch, remember Pathfinder rounds down and ties go to the ACTION (hit over defend, skill checks against DCs, etc.) It's part of the game. They made it.

Cevah |

Lets take you illistration and add some numbers for positions....
[extra wall added for thickness].
.
.
.
Jumping a 15' pit:
A123B
[]XXX[][]= solid ground (5')
X= empty space (5')Climbing a 15' wall:
B 4 3
[][]2
[][]1
[][]A
[][][][][]
You say that in climbing a wall you cannot be in position 3 because you are neither on the wall nor the ledge. Well, the same condition applies to the pit. Position 3 on the pit is not supported. Yet clearly I move through it to get to position B. Why would I not move through the wall position 3 to get to position 4? I cannot stop in position 3, as I would fall, but it is fine to move through.
/cevah

Cevah |

From post 21:
The reason i'm interested in the answer this time is to figure out whether you provoke from an opponent with reach that is standing 5ft from the edge. If the opponent was standing on the edge (position 3), obviously he'd threaten and you'd provoke moving onto the obstacle (into 3).
Edit:
Your right. I don't need that. For some reason I was thinking the wall climb was ending on a number and not a letter. Remove 4, and replace the reference with "B"./cevah

toastedamphibian |
toastedamphibian wrote:5ft step into John's Position 2, describe it as being on the edge of the cliff. Next turn 5ft step in. But your going to be flat-footed until you take that second step, probably not a great plan.
Or am I misunderstanding the question?
You did, according to john there is no position 2 if it's at the edge of the cliff. To avoid "W.C. syndrome.
So you'd have to 5ft step up diagonally, from his 1 to 3. Which is where my hard corner comes in.
Looks like you misunderstood the answer. DESCRIBE 2 as ON the CLIFF EDGE. Preferably place your grid such that the wall starts in a square, not directly on a line. In the event you cannot, say that it is. If it becomes a problem, remind them that the map is not a to scale 100% accurate representation of the action: the beds aren't actuall 10x12ft.
Treat it my way, the situation makes sense, and no rules are broken, but the miniature placement looks a little odd.
Do it the otherway, and what, break one clear rule to avoid breaking a less clear rule and get a slightly different mini placement while forsaking narrative sense?
I don't see the point. The grid is a tool, not the goal.
Edit: Incidentally, 2 is also the square someone at the top of the wall would need to stand to strike down at a climber.

Thaboe |

Toast, I understood what you were saying.
So you mean every drop is to cover 50% of the square so you can argue you can be both standing on the square as well as climbing it?
But that still doesn't resolve the other part of my problem. The reason I initially posted. If a wall is 15 ft high, and i climb 15 ft worth of movement, does that put me on top of the wall, or at the edge.
If the edge is a hard corner, you seem to need an extra 5 feet to move into a wall. Because you can't climb through the corner, but need to climb around it. So to climb on top of a 15 foot obstacle, you'd need to climb 15 ft, but move 20ft (1,2,3,B). As is the case with jumping a 15 ft wide pit. You need to cover the distance AND move into the safe square.
B 3
[]2
[]1
[]A
The main explanation I'm seeing for why it shouldn't be treated as a hard corner is because to climb a 15 ft wall would require you to only climb 15 ft, and that climbing those 15 ft WILL to put you on top of the wall.
And if needing only need to climb 15 feet to get on top of a 15 ft wall and the edge is treated as a hard corner, that means you'r not actually climbing from the bottom of the wall to the top in the 15 feet of climbing. Which is where my OP question comes in. Do we count the distance we need to climb from where our hands are, or where our feet at?
As for where you need to stand to strike down the climber. If you stand on the edge and climber needs to climb around the hard corner (through your 2), and that is the movement that would provoke from someone standing on the edge. Who will make the attack against the climbers flatfooted AC.
If the corner isn't a hard corner and i'm climbing through it, then climbing on top of a wall would never provoke because the edge is still providing you cover. Which just seems really off to me.

Komoda |
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Toast, I understood what you were saying.
Thaboel wrote:So you mean every drop is to cover 50% of the square so you can argue you can be both standing on the square as well as climbing it?But that still doesn't resolve the other part of my problem. The reason I initially posted. If a wall is 15 ft high, and i climb 15 ft worth of movement, does that put me on top of the wall, or at the edge.
If the edge is a hard corner, you seem to need an extra 5 feet to move into a wall. Because you can't climb through the corner, but need to climb around it. So to climb on top of a 15 foot obstacle, you'd need to climb 15 ft, but move 20ft (1,2,3,B). As is the case with jumping a 15 ft wide pit. You need to cover the distance AND move into the safe square.
B 3
[]2
[]1
[]AThe main explanation I'm seeing for why it shouldn't be treated as a hard corner is because to climb a 15 ft wall would require you to only climb 15 ft, and that climbing those 15 ft WILL to put you on top of the wall.
And if needing only need to climb 15 feet to get on top of a 15 ft wall and the edge is treated as a hard corner, that means you'r not actually climbing from the bottom of the wall to the top in the 15 feet of climbing. Which is where my OP question comes in. Do we count the distance we need to climb from where our hands are, or where our feet at?
As for where you need to stand to strike down the climber. If you stand on the edge and climber needs to climb around the hard corner (through your 2), and that is the movement that would provoke from someone standing on the edge. Who will make the attack against the climbers flatfooted AC.
If the corner isn't a hard corner and i'm climbing through it, then climbing on top of a wall would never provoke because the edge is still providing you cover. Which just seems really off to me.
I would rule that you can go through the hard corner, in terms of movement spent. It seems to me that the 1/4 speed helps to account for what is going on. Also, gravity is working at a different angle than when the hard corner rules are typically used.
I would rule that an AoO is appropriate. Maybe even two. One, when going over the hard corner, you are clearly at a disadvantage. The second would basically be for standing up from prone. If you intend to be standing when you climb over that edge, you are pretty much getting up from prone.

Thaboe |

You don't have the prone condition though. And if you climb at an incline, or a ladder, rather than a 90 free climb degree angle, you're not really 'standing up. Ruling like that would be way to rough imo.
The 1/4 movement is because it's supposed to be really slow and cumbersome. Just like swimming. And just like swimming, you can overexert yourself (increase the DC) to move at half speed.
Further more,the hard corner rules don't deal with gravity, the same would apply when you would be flying around an edge or a corridor corner or if you were standing in a wall with spiderclimb. Cover will remain cover. But if you can climb through a hard corner (and presumably 5ft step it if you have a climb speed), then perhaps you can also 5ft step through it with a perfect fly speed. Which again, is why i wouldn't want to rule that it isn't a hard corner.

toastedamphibian |
Toast, I understood what you were saying.
Then it would seem that maybe I still don't understand the question...
If you climb 15ft up, you are 3 cubes above the cube you started in. Your hands increase in altitude by 15ft, as do your feet and head. 3 spaces, straight up, 0 squares over. Such that you are "floating" but your not actually floating, your standing precariously on the cliff edge.
If you want to stop balancing on the cliff edge, move away from it following the normal movement rules.
I was not speaking before about hitting someone as they move away from the cliff face, but rather while they are still climbing, moving from space 2 to space 3 in your diagram. They would need to balance on the cliff face to attack straight down it or stand in B where their target will have cover from the wall.
The benifit of hitting them when they leave 2 instead of when they leave 3, is that leaving 2 is climbing, and the check to not fall when hit while climbing is higher than the DC to not fall while balancing.
In short: rotate the grid vertically, then follow all the movement and cover rules. Assume all walls pass the grid line a little for purposes of virsimilitude.