TLOS versus interposing units...

[Denzark]

Quick question - I would appreciate your general consensus and/or references.

Does true line of sight trump interposing units? If you fire at a squad of infantry behind a squad of infantry, that target will attract a 4+ save. But what if your target is big enough for a line to be traced from firer to centre mass without going through another minature?

The example I would give is my defilers are tall enough so that most enemy fire to centre mass is at an upwards angle, so never actually goes through a squad, so I can't screen with infantry.

Any comments?

[BuFFo]

In general, the defending unit won't get a cover save.

[Nabterayl]

If we're talking about a non-vehicle, non-monstrous creature unit, then yes, the unit is "in cover" if the line of sight from at least 50% of the firing unit to at least 50% of the target unit passes through an intervening unit.

To put that less generally:

Suppose unit A is firing at unit C. The line of sight from A to C passes between two models of unit B - but A has a clear line of sight to all of C.

C still gets the cover save. This is clearly spelled out on page 22 under "Firing through units or area terrain."

Similarly, if A is firing at C, and the line of sight from A to C passes through the legs of defiler B - but A has a clear shot through the legs of B - C still gets the cover save. A is still firing through an intervening unit.

However, all of this goes out the window when you start talking about vehicles or monstrous creatures, per pages 51 and 62. Vehicles and monstrous creatures work through the 50% rule. Page 22 is part of the normal cover rules; it is not an exception to the 50% rule.

So suppose unit A is firing at defiler C. The line of sight from A to C passes through unit B.

C only gets the cover save if B physically obscures at least 50% of C, from A's point of view. It does not matter that A is firing through a unit. The 50% rule is still the only one that matters.

[Nabterayl]

most enemy fire to centre mass is at an upwards angle, so never actually goes through a squad, so I can't screen with infantry.

You didn't actually ask about this, but I feel like I should point out that fire in 5th edition is not to center of mass. If a target [non-vehicle non-monstrous creature] model's toe is covered by a rock, that model is in cover, even though the firer has a wide open shot to the target's "center of mass." If a tank is visible through a window such that the top 25% and bottom 25% of the tank are obscured, that tank is in cover, even though the firer has a wide open shot to the target's "center of mass."

I point this out because in the case of a Defiler, the arms and legs are valid targets (see page 72, defining the arms and legs of a walker as part of its "hull"). So if you have a firing unit, an infantry unit in front of a Defiler, and then the Defiler, all on a level table, the firing unit's shots do pass through the intervening infantry unit. The Defiler still doesn't get a cover save, though, because the intervening infantry unit doesn't cover at least 50% of the Defiler (unless you have some really big infantry models, such as perhaps XV88s).

[Jwolf]

Defilers are a particularly good example of a model that is tall enough that shooting completely OVER intervening units is possible. Titans fire over intervening units very well, too - not that they fire weapons that care about cover much, mind you.

Most tanks are short enough that they can fire over units that are in BtB or very close to them, but otherwise clip some portion of the intervening models in the LOS from their guns to target.

[BuFFo]

Lol Nabterayl, neither of your posts answered his question :p

He is asking if the firing models is physically tall enough where LOS goes completely over all objects/models in such a manner that the defending unit is NOT behind 50% of anything.

To which the answer is no, they don't get a cover save.

This game is TLOS. If the defending unit not 50% blocked somehow, it gets no save, UNLESS you are drawing LOS THROUGH the gaps of intervening units, of which there is a picture in the MRB that address this rare instance quite perfectly.

Maybe I misread your answers? :confused:

[DarkLink]

Yeah, unless the Defiler is 50% blocked, it won't get a cover save. Vehicles only ever get cover saves from being 50% blocked. It doesn't matter if there are interposing units, unless those units are big enough to block 50%.

Also, it doesn't matter if you can draw LOS to the center of mass. Center of mass isn't considered in TLOS. In this case, the only thing to consider is the 50% blockage. If it were an infantry unit being targeted, you would also consider "is it standing in cover" and "do I have to shoot through an intervening unit to shoot it".

[Nabterayl]

He is asking if the firing models is physically tall enough where LOS goes completely over all objects/models in such a manner that the defending unit is NOT behind 50% of anything.
That's true, but only if the entire relevant area of the target is above the intervening unit. In the case of a non-vehicle non-monstrous creature unit, the relevant target area is the head, body, legs, and arms, so if LOS can be drawn through an intervening unit to the target's foot, you're still shooting through the intervening unit. In the case of a V/MC unit, the relevant target area is the least favorable 50% of the model.

[BuFFo]

The example I would give is my defilers are tall enough so that most enemy fire to centre mass is at an upwards angle, so never actually goes through a squad, so I can't screen with infantry.

I honestly don't know what Nab is on about, but simply put without any confusion, no, the defending unit would not get a cover save from your Defiler.

You draw LOS from model to model, not model to ground then along the ground to model.

[Cryl]

I've reread the responses here several times to make sure I'm reading things right and having done so I'm pretty sure that you're both basically saying the same and correct thing just in very different ways.

The point that I think that, Nabterayl is making (rightly) is that the issue of centre mass for a defiler doesn't actually matter with the way that TLOS and 50% obscured works, the issue is how much of the vehicle is or isn't obscured for the sake of a cover save.

In any case for the specific question you asked it sounds like the answers no as most infantry won't be tall enough to obscure enough of the defiler for the cover save

[Nabterayl]

The point that I think that, Nabterayl is making (rightly) is that the issue of centre mass for a defiler doesn't actually matter with the way that TLOS and 50% obscured works, the issue is how much of the vehicle is or isn't obscured for the sake of a cover save.
Yes, that's what I was trying to say. Centre of mass never matters for TLOS (in fact my personal shorthand for TLOS is "Draw line of sight in the way that is least favorable to the shooter").