CC on a ladder

Yes.

Base is in contact with the ladder. So the SIL is ~perpendicular to the wall.

Yes this means that someone at the top of a ladder behind a parapet can't be engaged by someone climbing the ladder (assuming the ladder isn't particularly wide).

Without a parapet and with perfect 90degree terrain then it's theoretically possible and, personally, I'd allow it in practice.

Edit: image added from General Movement Rules.

 

It can. But the Impetuous model can either Jump or Climb the wall to get into B2B instead.

 

Remember, you don't climb ladders, you move along them. It is a very important distinction.

 

Even better if the model at the top of the ladder is prone, they can't be seen or engaged by the model on the ladder, protecting them entirely.

 

The rules are really unclear as to what happens, exactly, when a model traverses a corner, like climbing from flat ground to a horizontal surface. It's possible you might be able to move onto the parapet and then back to the ladder, gaining LoF to the speculo, but who knows, and CB is not really in the habit of clarifying their rules issues.

 

Why wouldn't you be able to vault onto the top of the parapet and then move back to the ladder?

That's entirely congruent with the rules for vaulting and for moving on vertical structures.

You wouldn't be able to do that as part of an Impetuous Move though (just as you can't on a horizontal). For Impetuous the move stops at the furthest legal distance, it was discussed previously.

In the example given, the Impetuous path would be to Jump or Climb onto the roof.

 

As far as I can tell, the only thing that’s prevented is going straight over the end of the ladder into base contact, because that would leave the trooper with its base unsupported.

But like inane.imp points out, just before base contact you are able to vault across the parapet to reach a fully supported position on the side. Because troopers are allowed to vault over obstacles that are too thin for them to stand on, and that’s all the parapet is.

Then again, I’m a firm believer in “Either we agree to make that terrain piece playable by allowing engaging in that position (base contact across the parapet), or take that terrain piece off the table.”

 

Even if you could vault the parapet, which I think is fine, you still have a problem in not being able to move through an enemy model.

A model's base must be fully supported, and the model must stay on the ladder.

Given this, how are you getting into a position in which the model on the ladder has its base fully supported without moving through the enemy model?

The parapet is like having a low wall spanning the width of a narrow alleyway. Your model can't move laterally (because of the ladder/alley walls). You can move forward, toward the enemy model, and you COULD vault the low wall, but you can't end on top of the wall because it isn't wide enough to fully support the model's base, and you can't move through the enemy model.

So you're stuck. You can't get into BtB contact because of the wall and you can't vault it because that would require you to move through the enemy model (which you can't do).

You either play it RAW, or you make a house rule that says you consider those two models to be in BtB contact despite the intervening terrain element.

 

@MindwormGames you vault up. It costs you shitloads of movement, consoderong you need to stay fully clear of enemy model, so this adds roughly 2,4" instead of 1" to get up
Edit: slightly wrong values, but you get the gist

 

i don't mind with being stuck. A low wall in a narrow alleyway is a good exemple. Where will your biker go if there is a jersey barrier 1" before reaching the enemy ? You cannot vault over because your base is 40mm and would be stuck on the barrier when reaching base contact and if you stay behind the barrier you cannot then do a CC attack. Which is fine. It is called proper unit placement, if you are on a roof and want to fend off CC attackers, preventing them from having enough space to get proper footing on the roof to fight you is a sound tactic. No way they can make cc attacks while balancing on a railing.

 

(wrong post)

 

For the same reason that when you climb to the top of a building, you hop to the roof instead of starting with the tips of your toes on it and sliding in.

Though I guess one could make the argument that the position on the parapet that's actually reached is one where the back of your base is on the edge of the parapet and you're standing on the top of it, *over* the prone model at the top of the ladder.

 

That's not how vault moves.

It moves up and over the obstacle, you just don't measure the vertical movement.

So yes, whilst vaulting, you're standing on top of the parapet over the prone Trooper. You then Move backwards until you're fully supported by ladder again.

While on the Parapet you won't be in Base to Base contact but will have LOF.

There's also issues with vaulting along the parapet rather than over it, so the width of the ladder matters as well (consensus largely was if you need to tightrope walk along the parapet that's not on, but if you can seemlessly transition ladder-parapet-roof then it's legal).

http://infinitytheforums.com/forum/topic/50446-two-questions-blocking-ladders-dodging-mines/

 

@inane.imp It's not how vault moves, but the question is if you're still moving along the "wall/ladder" while on the parapet or not. It's unclear.

 

This same question was asked (by me) on the old forum. I think it went for three pages with no consensus reached. The only thing people agreed was that buildings which create this situation suck and it would be better to not use them ;)

 

I linked the thread above. I read it as we agreed the answer was "Sometimes you definitely can and sometimes you definitely can't. Where that line is depends on the terrain and model positioning. It's better to just design the problem away."