Neil:
I’ve just got a quick question about the combination of a Master Engineer, and a Grudgethrower with a Rune of Accuracy. The Engineer allows you to re-roll the artillery dice, and the Rune allows you to re-roll the scatter dice.
Is it permissible (and also acceptable) to re-roll one, and then depending on the result the other or do you need to either roll both together/choose to re-roll only one?
E.G. I roll an arrow and a 10. Can I first re-roll the arrow, to try to get the hit, then if this fails, re-roll the 10 to try to reduce the scatter?
Thanks
Thommy H:
You never have to use a re-roll, and since they’re seperate upgrades, you can use one, both or neither.
Unless the Dwarf book says different anyway.
Neil:
You never have to use a re-roll, and since they're seperate upgrades, you can use one, both or neither.
Thommy H
Thanks for the reply, but it's more the timing of them that I am interested in. If I choose to use both, must I roll them both together, or can I roll one, see what I get and then decide whether or not to use the other one?
nitroglysarine:
I think as you roll them both together, you must re-roll them both together, or just choose to re-roll one.
That would be in the spirit of the game, and I think that came up two editions ago with something similar.
But I may be wrong.
snowblizz:
I agree with Thommy (and the Dwarf books doesn’t say anything special about it), as the player it’s your choice what to use and in which order.
Usually when there are “timing issues” the FAQs say that the player whose turn it is decides the order of doing things.
Thommy H:
Do you only get to use the re-rolls once per game? I was under the impression, from my vague memories of Army Builder, that they could be used every time you fired - otherwise both upgrades are quite expensive for what they do. In which case, why does it matter what order the dice are rolled in? If you get a result on one you don’t like, just re-roll it.
nitroglysarine:
Am I misunderstanding the question, do you mean both dice when rolled aren’t what you want, so you re-roll the direction, don’t like that so then re-roll the distance after?
So order you are asking if is okay:-
1.Roll both once - both you don’t like
2.Roll one, don’t like that result,
3.Roll the other dice after.
(just to get it straight in my head)
Thommy H:
Oh, okay, I think I get it. You’re asking if, since you traditionally roll Scatter and Artillery dice together, whether you have to re-roll them together too. Is that right?
Because, as I said in my first reply, they’re seperate upgrades - the re-rolls aren’t linked at all, so just roll whichever dice you don’t like again, and then use your other re-roll if you still don’t like it.
Jumbster:
Yep, you can use the scatter and artillery reroll ability every time you shoot, but if you used a ME ability early in the turn, with the GT or other War machine, you cant use his artillery reroll.
Neil:
whether you have to re-roll them together too. Is that right?
Thommy H
That's right. Effectively if you have both it gives you two chances to get a favourable scatter result if you don't have to make your re-rolls at the same time. I can't see anything that would prevent it in the rules, it just seems like it would not be in the spirit of the game.
So in my example if my shot scatters 10" off target I can say, Ok I'll re-roll the scatter using the rune of accuracy, hoping for a hit. If it comes up with another scatter,
then I can then say, Ok I'll use the Master Engineer to re-roll the artillery dice, hoping to reduce the distance the shot has scattered and not to mis-fire.
Sorry if I didn't explain it very well.
nitroglysarine:
darn re-rolls can get complicated! 
Thommy H:
Effectively if you have both it gives you two chances to get a favourable scatter result
Well, you have paid the points for both re-rolls. Look at this way: if you had to do them both together, then both upgrades would be less effective. You'd essentially be paying points to nerf your own buffs. If you have an Engineer and a Rune of Accuracy on one machine, it
should be almost impossible to miss with it! That's the whole idea!
Hashut’s Blessing:
As Thommy H has said, it’s entirely possible to re-roll one and, if you find it still unsavoury, re-roll the other afterwards. They are separate re-rolls. It’s not like a Leadership test with a re-roll, they are different rolls altogether. One is a roll for scatter and one is a roll for distance scattered. Ultimately, you could roll the original rolls one at a time (to see if it is a hit or not before determing direction or to determine direction/misfire before distance/hit).