I figure we needed this somewhere.
http://anwu.org/games/dice_calc.html

x p(roll = x) p(roll > x) p(roll >= x) p(roll < x) p(roll <= x)
3 0.00463 0.99537 1 0 0.00463
4 0.01389 0.98148 0.99537 0.00463 0.01852
5 0.02778 0.9537 0.98148 0.01852 0.0463
6 0.0463 0.9074 0.9537 0.0463 0.0926
7 0.06944 0.83796 0.9074 0.0926 0.16204
8 0.09722 0.74074 0.83796 0.16204 0.25926
9 0.11574 0.625 0.74074 0.25926 0.375
10 0.125 0.5 0.625 0.375 0.5
11 0.125 0.375 0.5 0.5 0.625
12 0.11574 0.25926 0.375 0.625 0.74074
13 0.09722 0.16204 0.25926 0.74074 0.83796
14 0.06944 0.0926 0.16204 0.83796 0.9074
15 0.0463 0.0463 0.0926 0.9074 0.9537
16 0.02778 0.01852 0.0463 0.9537 0.98148
17 0.01389 0.00463 0.01852 0.98148 0.99537
18 0.00463 0 0.00463 0.99537 1

So basically, where X is the leadership. On a naked roll without re-rolls or cold-blooded, it is only a 50% chance that someone will roll higher than a 10. Here's another way to look at this.

Odds of rolling -
8 - 9.7%
9 - 11.6%
10 - 12.5%
11 - 12.5%
12 - 11.6%
13 - 9.7%
14 - 6.9%
15 - 4.6%
16 - 2.8%
17 - 1.4%
18 - .5%

Odds of taking ANY wounds without BSB (i.e., roll higher than LD).
LD 7 - 83.8%
LD 8 - 74.1%
LD 9 - 62.5%
LD 10 - 50%

Odds of taking ANY wounds with BSB.
LD 7 - 70.2%
LD 8 - 54.9%
LD 9 - 39%
LD 10 - 25%

So to kill a Dwarven war machine with LD 9 and no BSB, you add up the odds of rolling 12 through 18 (37.5%) (which represents Roll - LD9 >= 3 wounds of crew). With a BSB, you take the percentage and multiply that by the sum of the odds of rolling 10 through 18 (representing first LD test failing), which is 62.5%. That means the odds are 23.4% of successfully killing a Dwarven war machine with BSB in one shot.

So with high LD armies around, especially with a BSB and LD10 general, you really have to ask yourself is it worth chucking dice. Killing the LD9 Dwarven war machine with BSB is 23.4%. A LD10 war machine with BSB is merely 12.95%.

If we didn't have that 3+ bounce, the Casket would be almost useless against most armies.

great topic-topic, huge help when making that kind of considerations. You should submit this to the tactics sticky right away and put it under the to be created statistics header. :)

I might disagree with you on the conclusion that it's useless on most armies, though. Armies I would be happy to use it against include
-goblins
-skaven (targets without ranks of course)
-chaos (armor go home)
-bretonnia (armor go home)
*of course they have relatively high LD, but wasting only two knights per turn is still worth it, if only in terms of points and for the psychological target as well.*
-beastmen
-ogres
-deamons, no idea about LD, but the casket negates the ward save and the deamons seem to have all though ridiculous single model drops
-vampires, "kill kill kill, kill those ethereal units"

cases of doubt
-dwarves, high LD, but we neeeed to kill the guns


Wouldn't like to use it against
-lizards, for obvious reasons
-high elves, mostly high LD rank and file
-dark elves, idem
-wood elves, idem, though the casket is handy for targetting.

in all the elve cases: bring bows, though.

still worth it for the D3 extra PD, and if want, you can choose to only cast it on ~2 dice and hope the enemy waste his dispel dice, it will also draw alot of cannon fire if you put it in the open, and there is the T10 really helpfull.

*Agrees with last post*

casket works just fine against woodelves, especially against treekin and treeman

ow, right, the forrest spirrit ward dies to magic!

Casket doesn't negate ward saves. It only negates armor.

You have to note to your opponents that the Casket rules state it is a leadership test and the BSB's hold your ground rule is not optional. In other words, they cannot choose to accept a failure of a LD test by 1 if the BSB is around. They must re-roll the entire result for better or worse.

That said, my point is that the Casket's effectiveness is severely reduced by the presence of a BSB. This makes it somewhat more unreliable than a conventional war machine but also much more devastating as many players can attest. The power dice alone make it worth taking. At the same time, fellow TK players need to also consider whether saving 2 dice for the casket is worthwhile, as opposed to channeling into some other spell which may be more useful. For non-TK players, the odds are a nice reality check into how powerful the casket actually is. Your dice may vary.

I don't know if anyone else tries this ever, I tried using Arkhan the Black in a tournament and coupled with Casket, it just makes for a really strong magic phase and the access to Doom and Darkness makes the Casket and SSC very strong.

I think that if you cast Doom and Darkness on the General's unit that it transfers the -3 LD to units around him as his LD becomes theirs but even if this were not the case, casting it on some units on the fringe with doom and darkness really hurts.

The Doom and Darkness combo with the General doesn't work as well anymore.

From the FAQ:
Page 107 – The General, Inspiring Presence
Change “within 12" use his Leadership instead” to “within 12"
may use his Leadership instead”

So if the General's leadership is lower than the unit's, they may choose not to use that leadership.

Tree spirit ward saves are negated if hit by magical attacks, ergo the Casket ignores their ward saves too.

I made up a big excel chart showing exactly this and more (spell-casting odds, Ld odds, etc), many moons ago. Has been very helpful for determining how many dice to chuck at spells or the probability of making something fail.

what veritas said about the wards

I don't feel the ASbearer does anything severe. for a LD 10 unit the chance on any damage goes from 50% to 25%, but the rolls are completely independent so the chance that you go from 1 wound to a reroll to 4 wounds is as big as the chance to go from 4 to 1, in a fatalistic way of speaking (I know the chances are more complex than that)

for a LD 7 unit, when you roll a measly 8, the BSB provides you the chance to actually roll more!

furthermore, you have range 48, and the BSB has range 12. let him worry about his formations, opportunity will be everywhere anyway. (should be a rule of aquisition, that one :D)

Also works fine on Mournfangs on the flanks, I can attest to :)