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Author Topic: (Answered) Timing of streak ammo expenditure  (Read 897 times)


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(Answered) Timing of streak ammo expenditure
« on: 16 February 2018, 18:22:11 »
Recently I've posted the following errata for BattleMech Manual:

P. 31 Shots - Ammunition Use Timing

Problem: Ammunition Use Timing in the Shots section on p. 31 instruct to mark off ammunition as soon as the attack declaration is made. It can't be correct for streak missile launchers, which fire only in case of a successful attack roll (made some time after the attack declaration is made). In case of a failed roll no ammunition is fired, so at the moment of the attack declaration players don't know if the ammunition needs to be marked off.

Solution: Add a sentence to the Ammunition Use Timing paragraph explaining when expenditure of streak ammo should be marked on 'Mech Record Sheet. My guess is that it should be done as soon as a successful attack roll for a streak luncher is made.

Then I've realised, that the solution I've suggested is not without it's own problems. Using it would mean, that if a unit takes a critical hit at streak ammo bin during Weapon Attack Phase the amount of damage from internal explosion may depend on weather the damaged unit already resolved it's attacks during this phase (and potentially fired streak missiles from this bin) or not, which is another break from the general rule that all attacks made during the same phase should be resolved as if they happened simultaneously, but since there are more situations in the game, that break this general rule it is probably not a big issue.

A bigger problem would be what to do with a unit, that declared an attack with a streak luncher, and lost all of it's streak ammunition (or at least so much of it, that it can't feed all streak launchers it declared to attack with during the current phase) before it can resolve this attack. Should a unit in this situation still be allowed to resolve such attack? If the answer is yes it could lead to a slightly wired situation, where the same shot of streak ammo may explode inside the unit carrying streak missiles, and hit the target of a streak missile attack damaging two 'Mechs during the same turn. If the answer is no, than streak launchers would become the only weapons on the game, that can be declare to attack during an attack phase, and then be denied a chance to resolve it due to damage the attacker has suffered during the same phase.

So in light of the above problems what should be the timing of streak ammo expenditure, and how should timing problems between it, and ammo destruction (especially due to critical hits) be resolved?

As a side note my errata for p. 31 BMM basically also applies (with all of its problems discussed above) to the last paragraph of p. 103 TW, which instructs the player to mark off expended ammunition "when the attack is declared", which can't be done for streak missiles for the reasons already explained above.


Edit: I thought some more about the problem of marking off ammunition on attack declaration, while being uncertain if any ammo will be fired, and it appeared to me, that it is not a problem exclusive to streak launchers, bat may apply to all ammo-dependant weapons. p. 25 BMM, p. 106 TW, and p. 35 Intro Rulebook all agree, that if after declaring an attack but before you make a to-hit roll, you realise that your modified to-hit number is above 12, you can declare not to attack, saving ammo, and heat build-up.

The problem with this rule is the same as with STREAKS - you could potentially declare an impossible attack, mark off the ammo for it, then take a critical hit at the ammo bin which had contained the ammo you marked off, and then when your attack comes - having to "return" ammo to the destroyed bin, which rises a question of how much damage you should have taken from internal explosion (if the ammo in question is explosive), since the ammo was marked off, when you took the critical hit, but later it turns out, that the ammo in question should have stayed in the bin all the time.

If the ammo that is marked off, but then ends up not being fired because of the "you can cancel an impossible attack" rule ends up not damaging a 'Mech during an internal explosion, that accrues before the 'Mech in question resolves its attack, then this rule is potentially abusable. I could for example take my King Crab, and on a turn I have no good targets and want to save ammo declare attack with it's AC/20s at a target I know will turn out to be 13+ to hit with those ACs just to have less ammo inside of my 'Mech for a part of the weapons attack phase, and potentially taking less (or even no) damage from internal explosion of bins containing my AC/20 ammo if they happen before it is the turn to resolve my Kong Crab attacks. The situation becomes even more funny if we rule, that if an ammo "returns" to a bin destroyed by a crit you need to correct the damage from the internal explosion that accrued earlier. In this case I could say "I'll just fire those guns and take the heat for it, but avoid the increased damage to my 'Mech".

A related problem with the "you cancel an attack if there is no way it can hit" rule is that if you have multiple weapons that are fed with the same ammo type, and you fire them all at different targets feeding them from different ammo bins, and then one of the targets turns out to be impossible to hit, and you take a critical hit to one of the ammo bins in the time between attack declarations and your attack resolution you have problem of determining if the ammo for the weapon(s) you didn't fire came from the bin that wasn't hit or not. The way I see it you could do it in one of four ways:
  1. Decide which particular bin feeds which particular attack when you declare them. It is a bad way, because it slows down play (you need to remember which of the identical weapons is targeted at which unit and fed by which ammo bin);
  2. Let the player controlling the unit, which has suffered a crit to the ammo bin decide if the ammo fr an attack that turned out not to happen came from that bin or not. It is a bad way, because it can be abused in the way I described in the paragraph above;
  3. Let the player who scored the critical hit decide. It is also a bad way, because it can be abused in the exact opposite way (and potentially puts units carrying multiples of the same ammo-fed weapons at a disadvantage);
  4. When a crit to an ammo bin happens determine randomly which shot from the unit that was hie came from which bin. It is probably a little better than the previous ways, but still does not fix all the problems (like declaring attacks against impossible targets  to have an option of saying "I will fire anyway just to spend the ammo and reduce or even avoid damage from an internal explosion" in case a crit to tan explosive ammo bin happens before an attack declaration and resolution).

Ultimately I realise that all of the above shenanigans could be avoided in one of two bad ways:
  A. by ruling, that you spend the ammo not during the attack declaration, but after making a to-hit roll (a successful to hit-roll in case of streaks), but it would put units that fire later in the initiative order at a disadvantage (because they could loose their ammo and suffer extra internal explosion damage just because they didn't have a chance to spend it's ammo) which goes against the general rules intention of making the damage resolution as independent on the sequence of attack as possible (the "all attacks and damage during each phase happen simultaneously" approach);
  B. by ruling that all ammo spent during any given phase still counts towards the damage from internal explosion that happen during that phase, but it could lead to a wired situation where a given shot could damage two units during the same phase - one it was fired at (as a result of a successful attack), and one it was fired from (as a result of an internal explosion). It would also result in having to remember which ammo bins were used during each phase until the end of that phase, which in most cases would just slow down the game, and add to the already quite long list of the things the players need to remember while playing.

Still leaving the ammo expenditure timing rules the way they are now create problems I describe above, so maybe some changes or clarifications (particularly about what happens if you crit an ammo bin, that you marked ammo off, and later in the phase it turns out this ammo didn't end up being fired) are needed?

I also realise, that the "you can cancel the attack if it turns out to be impossible" rule is meant to be used during friendly games to speed them up by having people prone to "analysis paralysis" worry less about their attack declarations (otherwise some of them would likely calculate all of their to-hit numbers twice - once before the attack declarations to make sure, that they aren't just wasting their ammo and generating heat for attacks that can't hit, and the second time, when they are about to roll to hit, if they already forgot the result of their previous calculation), and during those super competitive matches this whole rule should be banned, because of potential abuses, but as I hope I've explained above clearly enough, not all problems with timing ammo expenditure come from this particular rule.
« Last Edit: 27 March 2018, 13:17:53 by Xotl »


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Re: (Research) Timing of streak ammo expenditure
« Reply #1 on: 27 March 2018, 13:17:46 »
We'll be making a small note to the Ammunition Use Timing about the exception for Streaks.  With regards to the needing 13+ issue, this is something that is pretty much self-moderating: people realize generally at the moment of firing or slightly thereafter that they can't hit, and so either don't make the attack or abort it a few seconds later.  It doesn't seem worth all the text to deal with such an obvious issue.
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Re: (Answered) Timing of streak ammo expenditure
« Reply #2 on: 27 March 2018, 17:49:35 »
Thanks for the answer. I'm looking forward to seeing how you solve a problem of critically hitting streak ammo bins on a unit which is yet to fire this turn. Not that it matters in most cases. It is just my love for such little rules details speaking here.

As I've stated above, my only concern about the 13+ rule is that some people may use it to intentionally declare impossible attacks with an intention of calling them back later, just to have as little ammo as possible in their ammo bins for part of the firing phase in case of ammo crits. I guess if you run into a Munchkin who plays like that, and refuses to change, you should look for a different gaming partner.

I personally avoid this issue by calculating to hit numbers when I declare an attack, and writing them down on Record Sheet's margin next to the weapons fired to avoid recalculating them if I forget them before it is time to roll. This way it is obvious if you can hit before you mark off the ammo (so you can abort the attack before it is a problem), and In my experience can actually speed up the game, since this way for each attack - target pair you calculate most of the to-hit modifiers first, and then only add range and other weapon-specific modifiers for each weapon. When I tried to calculate those same numbers just before rolling it turned out sometimes, that I calculated a to-hit number for one weapon, rolled for it, got plenty of cluster hits and/or crits to resolve, and by the time I got to checking if the next weapon hit the same target I already forgot the original to-hit roll, forcing me to recalculate.
« Last Edit: 28 March 2018, 03:49:34 by Alfaryn »