In a recent game, an enemy (a genestealer broodlord, specifically) was on a catwalk some 40m above the kill team- We fired at the thing with a krak missle, struck cover... The issue we're having, is that nobody believes that the cover could withstand this, cause quite an argument..

The question, as concise as i can make it- When firing weapons that vastly outclass the cover a target is hiding behind, (Say, a flimsy door worth 3 and a las cannon) is there a rule concerning the cover being completely destroyed rather than being reduced by one, if so, where? and if not, why not?

Yes,

From DW Core Rules page 246

"Cover is not invulnerable. Attacks can damage or destroy the
protection afforded by cover. Each successful hit against cover
that deals any amount of Damage in excess of the Armour
Points it provides reduces the cover’s Armour Points by 1."

Once its Armour points are reduced to 0 it no longer affords cover, yes?

So if a Heavy Bolter is used on Ap3 cover and scores three hits that exceed Ap3, then 2 then 1, the cover is shredded. (Of course those three hits are from one marine in one round and the cover is scragged)

He's asking if a weapon that does 40 points of damage to a drywall wall (cover 2 lets say) would the whole wall just be totally destroyed.

The answer is complicated. Your lascannon wouldn't destroy your example door, or my drywall wall. The reason is over penetration. It would punch a hole in the door (decreasing the cover of the door as per the rules, from the hole), but it wouldn't blow it down. A blast weapon on the other hand may blow a door down even if it doesn't do a massive amount of damage over the door's cover rating. The overpreasure from the blast would knock it off its hinges. If you shot at my drywall wall with bolters the rounds would go right through leaving little holes (the rounds traveling too fast to detonate on impact with such a soft target), but if you hit it with a frag grenade from a launcher it would blast a huge hole in the wall (a hole large enough to negate its cover to anything directly behind it).

Now not every door, or cover, or weapon is made equally. Some doors, and cover may hold up better to certain weapons that could normally do a lot of damage. And vice versa, some weapons should be more effective against certain materials. You wouldn't use a grenade launcher or a lascannon against a large fortress wall, you'd plant a demo charge at its base to blow a hole in it (thats what demo[lition] charges are for after all).

These things are the purvue of your GM. The GM's role is to determine how these "cinimatic elements" play out. As a GM myself I apply my real life military, weapons, and weapon effects knowledge to my games (truth is stranger than fiction after all), but yours can play it out however he feels like it.

Just a tip though GMs, try to keep things consistent. If a grenade blows a wooden door off its hinges one night, it should the next night. Of course metal doors are a different matter ;-).

He was asking for an existing rule. There isn't one, so instead of relyong on GM fiat I pointed out the way cover can be reduced - almost instantly - by a single weapon under the current RAW. You are correct to point out that 'stuff happens' and he should be consistent.

As herichimo says, firing a lascannon at someone in cover isn't necessarily going to obliterate that cover entirely - it'll put a hole in there (reduced protection from cover), but a lascannon beam isn't going to completely destroy a wall due to an incidental hit caused by firing at a target in cover.

In the past, I've considered two different house rules for blasting down terrain. The first is to use the weapon's Pen as the amount the cover is reduced by, though the effect of that tends to be really quite extreme and makes most common cover worthless in a round or so. The other is to allow weapons with the Blast quality to remove a number of additional points of AP from cover equal to the size of the Blast (so a Blast (2) weapon removes 3 points of AP from cover instead of 1) due to the blast affecting a larger area. You might want to go further and add additional bonus cover removed for things like the Concussive quality (a Thunder Hammer's shockwave being more destructive to surrounding objects than cutting with a chainsword) or dealing Explosive damage (a bolter will put a bigger hole in a wall with each shot than an autogun will because those shells are exploding).

N0-1_H3r3 said:

im the GM at the OP's table and since i didnt have anything on the spot i just went with RAW as everyone at that table is pretty new to the system. that said i really like the blast weapons remove an additonal amount of cover equal to their blast.

one idea i haven't tried out yet is that for every amount of damage that equals the AP of the cover, reduce it by one. for example, a single hit of 25 damage making it through cover with AP 5 would destroy the cover, just as if it had been hit with 5 hits for 1 damage. Seem a little silly that the only way to break objects was a number of hits equal to it's AP, no mater how heavy a blow you could land.

I think we need to remember that the entire force of the blow isn't hitting the cover, the cover is simply reducing the damage that the target takes. If I was GMing with ThethatGuy's rule I wouldn't damage the target any way, since all of the attacks damage seems to have been spent destroying the cover. But that's just my take on it. BUT, with that said, as this a roleplaying game if I was in the OP's GM's position I'd have given the Krak Missile a chance (some sort of roll based outcome) of being blown out from under the Genestealer, dropping the bugger to whatever lay below... maybe a acrobatics/agility test on the part of the Genestealer to see if he avoid falling.

Hello.

I also think the rule of cover destruction is a little bit unrealistic. If three missiles hit a door with AP 3, I do not think all three missiles are required to destroy the cover completely. This rule should be readjusted.

With best regards.

Tricky part is we need some sort of sliding scale including damage and Pen; frag missile blows down a door, but bounces off a concrete bunker, which a multi-melta then toasts.

Geistwandler said:

Well, that depends - is the missile punching a hole in the door to kill the guy behind (reducing its effectiveness as cover as a side-effect more than anything else), or is it simply detonating against the door? In the former case, it's damaging cover (which covers incidental damage to objects people are hiding behind), in the latter, it's something else entirely.