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Saben
16-03-2008, 17:55
Okay. For all the mathematicians out there- up for a challenge?

Assume a basic Vampire Lord. WS 7, S5, 4A. Assume he's against a standard man character. WS 6, T4, 2+ save.

What is the probability of getting an instant kill with the Frostblade (one unsaved wound= dead) compared to Killing Blow.


Now understandably the main strength of the Frostblade is against Dragons, Treemen and other large nasties, but I'm just curious about it's lord-killing power compared to Killing Blow. Also models immune to KB are not immune to Frostblade so that's another point in its favour... But it is still 4x the cost.

tdh6002
16-03-2008, 19:29
the frostblade has twice as more chance to instant kill the character then the SoK.

Frostblade
4*2/3=2.67
2.67*2/3=1.78
1.78*1/2=0.89 wounds on the target that does instant kill.

Sword of kings
4*2/3=2.67
2.67*2/3=1.78 ( there is a 44% of killing blowing the opponent(2.67*1/6=0.44)
1.78*1/2=0.89 wounds on the target that doesn't instant kill.

so there you have it, for 4x the price you have 2x the change of instant killing a character.

GodHead
16-03-2008, 19:38
Unless there is an armour save. In which case the Frostblade wounds will be reduced by the armour save of the target, while the Killing Blows will ignore it.

theunwantedbeing
16-03-2008, 19:50
The sword of kings is better against opponents with very high saves and those with only 1 wound. The frostblade is better against things with lots of wounds but not that great saves.

You give the sword of kings to a wight king and go head hunting anyway, the frostblade is for monster slaying.(so brilliant vs ogres)

joseph4469
17-03-2008, 00:42
Would the frostblade kill 3 ogres if it did 3 wounds?

Saben
17-03-2008, 00:58
Yes, following the rules for Multiple Wound Casualties on page 31 of the BRB each Ogre is hit by 1 "wound" the weapon then inflicts 3 wounds for each Ogre it wounded for a total of 9 wounds. So you remove 3 Ogres.

In all honesty Frostblade seems a bit of a waste for its points compare to just a Sword of Kings unless you know in advance you'll be playing against a monster, treeman, lightly armoured heroes or multi-wound, US3 models like Ogres. Then again, given VC don't get any War Machines to take out such targets maybe it's just what the doctor ordered?

GodHead
17-03-2008, 01:00
Frostblade, Flying Horror, Infinite Hatred, Beguile, Avatar of Death and he's in a unit of marching Ghouls.

Wow that's a cruise missile if ever there was one. You'll kill their general/dragon/big pointy thing in the first turn every game.

"Ta da!"

mightygnoblar
17-03-2008, 01:06
its also is a nice way of making short work of the stank army of doom

Dalamyr the Fleetmaster
17-03-2008, 19:26
I would always go for the frostblade because eventually there going to fail one armour save then poof down goes the character

Malorian
17-03-2008, 19:33
Frostblade is just too many points in my books. Maybe it's just me, but I don't see many monsters or ogres to use it against.

Dalamyr the Fleetmaster
17-03-2008, 19:37
my store has loads of ogre players so it's just the ticket for me

Atzcapotzalco
17-03-2008, 20:30
Assuming hitting on 3+, wounding on 3+ and saving on a 4+ (2+ with a -2 modifier), the frostblade has a 2/9 chance to instant kill per attack, as opposed to 1/9 for sword of kings.

Increased armour/toughness favour sword of king. Say, a dwarf lord with a 1+ save you're looking at 1/12 per attack each. Of course, with the increase in killing blow availability more people are taking out protection against this, whereas the frostblade works against all.

athamas
17-03-2008, 20:35
but you should be hitting on 3's with rerolls, wounding on 3's with rerolls, and then there is just the armour to get through...


is no god for hero hunting.. but great against giants and the like..

what hapens with red fury though?

Spirit
17-03-2008, 20:59
its also is a nice way of making short work of the stank army of doom


Ok, next question, what are the chances of a flying vamp with infinite hatred charging a Stank actually killing it?

5 attacks, auto hit (so ok, you don't need hatred.. lol) and 6s to wound with a 3+ (1+ -2 is correct i think).

And you get 2 rounds of combat against it, because it wont kill you in your turn..

But if you dont kill it, you lose the game.. Lol

mightygnoblar
17-03-2008, 23:03
Ok, next question, what are the chances of a flying vamp with infinite hatred charging a Stank actually killing it?

5 attacks, auto hit (so ok, you don't need hatred.. lol) and 6s to wound with a 3+ (1+ -2 is correct i think).

And you get 2 rounds of combat against it, because it wont kill you in your turn..

But if you dont kill it, you lose the game.. Lol

its only four attacks actually but your only needing fives to wound the thing, then it fails just one armour save and bang, there goes ten wounds :evilgrin:

xragg
17-03-2008, 23:23
the frostblade has twice as more chance to instant kill the character then the SoK.

Frostblade
4*2/3=2.67
2.67*2/3=1.78
1.78*1/2=0.89 wounds on the target that does instant kill.

Sword of kings
4*2/3=2.67
2.67*2/3=1.78 ( there is a 44% of killing blowing the opponent(2.67*1/6=0.44)
1.78*1/2=0.89 wounds on the target that doesn't instant kill.

so there you have it, for 4x the price you have 2x the change of instant killing a character.


This included armor saves, thats what the last line is in each part (1.78*1/2).
to hit
to wound
armor save

Although it doesnt change the instant death comparision, the last line of the SoK is wrong. It should be 1.34*1/2=0.67 wounds on the target that doesn't instant kill (since the killing blow wound has already killed you). 2+ is a really good armor save, the worse that gets, the more the Frostblades shines in comparions to SoK.

4 hits onto a Stank, needing 5's to wound, 3+ saves... Basically, thats 1 in 9 hits that will destroy it outright. On average, it will take you 2.25 rounds to kill it (the time it takes you to do 9 attacks). Find an extra attack somehow and it will take you 1.8 rounds to kill it. Find an extra point of strength and it will take you 1 round to kill it. This is all averages and of course you can kill it in 1 round or never if roll bad enough.

Lord Inquisitor
17-03-2008, 23:29
Okay. For all the mathematicians out there- up for a challenge?

Assume a basic Vampire Lord. WS 7, S5, 4A. Assume he's against a standard man character. WS 6, T4, 2+ save.

What is the probability of getting an instant kill with the Frostblade (one unsaved wound= dead) compared to Killing Blow.


Now understandably the main strength of the Frostblade is against Dragons, Treemen and other large nasties, but I'm just curious about it's lord-killing power compared to Killing Blow. Also models immune to KB are not immune to Frostblade so that's another point in its favour... But it is still 4x the cost.

No-one’s done this properly.

The vampire hits on 3’s, wounds on 3s and has a -2 armour save modifier.

Probability of killing the target with a frostblade
P (killing the target) = 1- P(not killing the target)
P (not killing the target) = (Probability of one attack failing to wound)^4
Probability of one attack failing to wound = 1-(Probability of one attack wounding)
Probability of one attack wounding = 2/3*2/3*1/2 = 4/18 = 2/9

Probability of killing the target with a frostblade = 1-(7/9)^4
= 0.63
=63%

Probability of killing the target with a killing blow for a single attack: (2/3*1/6)=2/18=1/9
Probability of not killing the target outright per attack = 8/9
Probability of killing the target in one combat round with the killing blow ability = 1-(8/9)^4
= 0.38
= 38%

However, these calculations don’t take into account the fact that you could kill the Empire hero outright with the non-killing-blow attacks just by scoring three or more wounds. Which I can’t be bothered to factor in because it would get messy.

xragg
18-03-2008, 00:18
In my defense, I never said my numbers were probabilities or percentages, just how long it would take assuming the dice rolls were evenly distributed (ie in 6 rolls of a die, you get one 1, one 2, etc). This is of course is not what ever happens. Probabilities factor in that dice dont distributed evenly at the expense of more math. For quick-simple comparisions, assuming even distribution will tell you which is better, where probabilities will tell you how much better.

Edit: I guess the OP asked for probabilities and just not which is better, so nevermind, lol.

Saben
18-03-2008, 00:46
Lord Inquisitor- I was actually thinking that. I remember back to my year 12 maths and remembered that to calculate the probability of at least one event (out of 4) occurring you need to subtract the probability of the event NEVER occurring from 1.

It's all coming back... :P

Now if we factor in Infinite Hatred and Beguile:
P(hit)= 2/3+(1/3*2/3)=8/9
P(KB once hit)= 1/6+(5/6*1/6)=11/36
P(hit and KB)= 11/36*8/9=22/81
P(no outright kill)= 59/81
P(KB with 4 attacks)= 1-(59/81)^4= 71.85%

Now Frostblade with the same:
P(hit)= 2/3+(1/3*2/3)=8/9
P(wound)= 2/3+(1/3*2/3)=8/9
P(no save)= 1/2
P(wounding)= 8/9*8/9*1/2=32/81
P(no wound)=49/81
P(kill)= 1-(49/81)^4= 86.60%

I think Beguile is really what makes KB shine and almost catch up in this case... I think you could even do with without Hatred, too.


As for the Frostblade versus a STank in a single round:
P(wound)=1/3*1/3=1/9
P(no wound)= 8/9
P(kill)=1-(8/9)^4=37.5% chance
Assuming 2 rounds of combat (before it crumbles your entire army)
1-(8/9)^8=61% chance

Thanks, Lord Inquisitor for reminding me of probability, it's been 6 long years...

vorac
18-03-2008, 03:12
there are cheaper ways of killing a Steam tank or a Treeman than using the Frostblade

How about the Balefire Lance 10 pts., add Red Fury and infinite hatred and i don't see how either would survive, the Steam tank might need 2 Rounds but the Treeman is going down first turn. 4 Attacks hitting on 3's wounding on 3's with no save at all and you get extra attacks for each wound, not to mention that each wound is doubled :) pure evil.

sulla
18-03-2008, 03:34
Increased armour/toughness favour sword of king. Say, a dwarf lord with a 1+ save you're looking at 1/12 per attack each. Of course, with the increase in killing blow availability more people are taking out protection against this, whereas the frostblade works against all.

Take care though, as a Dwarf can be made immune to killing blow thorugh runes. In those cases, the sword of kings is completely worthless.



there are cheaper ways of killing a Steam tank or a Treeman than using the Frostblade



Don't forget the humble great weapon and the extra attack bllodline... Doesn't need the charge, can be duplicated on every vamp in the army making every infantry block a trap for tanks and chariots...

eleveninches
18-03-2008, 10:31
its also is a nice way of making short work of the stank army of doom

not if he has enough steam points to crush your lord and make the army crumble before you can hit it back

Spirit
18-03-2008, 13:08
What is the toughness of a steam tank? I was under the impression it was 7, but someone said you needed a 5+ to wound it with a frostblade...

And could someone give me the odds of killing it with your 4 attack vamp lord?

Saben
19-03-2008, 00:03
What is the toughness of a steam tank? I was under the impression it was 7, but someone said you needed a 5+ to wound it with a frostblade...

I'm going off Army Builder which says it is T6, I don't have the Empire Book...


And could someone give me the odds of killing it with your 4 attack vamp lord?

Read at the bottom of the previous page- I did this already:



As for the Frostblade versus a STank in a single round:
P(wound)=1/3*1/3=1/9
P(no wound)= 8/9
P(kill)=1-(8/9)^4=37.5% chance
Assuming 2 rounds of combat (before it crumbles your entire army)
1-(8/9)^8=61% chance


37.5% chance in a single round of combat, 61% chance after two rounds.

Spirit
19-03-2008, 00:42
Hmm, think il give that a go, but i'll put him in a unit of skeletons, there is a very annoying empire player at my LGS and i don't see what hes gonna do against that, even with only 61%, he then only (only! lol) gets 5d3 hits, so thats what? 10? i can survive that with 4 ranks standard and outnumber!

And thank you, sorry i missed it the first time.

Lucky24/7
19-03-2008, 10:09
Still think flaying campire of death is a better option but thats just me. but thats ventering into relms of lords which we could be here all day talking about :D

Krankenstein
19-03-2008, 23:19
Take care though, as a Dwarf can be made immune to killing blow thorugh runes.


Quite. And Bretonnians. And Vampires.