This might belong in the FAQ/Errata thread, but my post is pretty long-winded, so I’m putting it here.

The Flamer has the Damage Effects of Burst, Persistent and Spread, so please tell me if I am calculating Damage correctly.

Linda the Super Mutant is standing in a Zone with 12 unarmoured Garys. She attacks one of the Garys and hits. She rolls 3CD Damage and uses the weapon’s Fire Rate to add 4CD extra to her Damage roll. Let’s say she rolls all 7 Effects.

She does 7 Damage to the first Gary.
Her 7 Spread Effects also hit Gary#1, each Spread Effect hitting a new random location on his body and inflicting half Damage, rounding down. So Gary#1 takes 7+7(3) = 28 Damage on Linda’s Turn.

Then we resolve the 7 Burst Effects. 7 additional Garys in the same Zone can be targeted for an extra hit. Linda looks at her ammo and chooses to hit an additional 4 Garys, spending 4 Flamer Fuel on top of the 5 Flamer Fuel she spent on her initital attack. All 4 additional Garys hit by Burst take the full 7 Damage Linda rolled in the initial attack.

Now we’re left with Persistent to resolve. Linda rolled 7 Effects. So, for the next 7 Rounds, at the end of each of his Turns, only Gary#1 suffers Persistent Damage. This is equal to the weapon’s Damage that was rolled in the initial attack (7), and no new rolls are necessary.

Unless Gary#1 can make an Attribute Test to stop the flames, he will take 7*7 = 49 Persistent Damage. So, ultimately Gary#1 takes 28+49 = 77 Damage and Gary#2-5 each take 7 Damage (all of it Debilitating.)

At least this is my understanding. Effects don’t act on Effects and Modiphius wants us to roll as infrequently as possible?

One correction: secondary hits from Spread aren’t counted for the purposes of Persistent, only the initial damage instance caused by the attack.

So:

You roll damage against the initial target, spending 4 ammo to boost damage up to 7 dice. The roll is, miraculously, 7 Effects.

The main target, Prime Gary, receives 7 Energy damage, plus 7 additional hits for 3 damage due to Spread. Those are resolved separately against the target’s Energy Resistance (i.e., it’s not a flat 28 damage, if the target has Energy Resistance 2 on all locations, then that only works out as 12 damage overall - this is why Spread and Piercing are a dangerous combo)

Due to Burst, up to 7 additional Garys can also be hit for 7 damage (up tp 1 per Effect rolled, costing 1 ammo for each additional Gary hit).

Due to Persistent, in subsequent turns, Prime Gary suffers the weapon’s damage, for a number of turns equal to the number of Effects rolled: in this case, 7 damage for 7 turns.

Would you say that this iteration of the 2d20 system is clinging too close to the FALLOUT 4 (video game) rules? Because an example like this sure makes it seem like it.

I’ll just say it’s not the 2d20 rules inherently. I have a flamethrower-wielder in my A!C 2d20 campaign, and he has none of this mechanical complexity.

Thank you very much for this clarification. Very helpful. But your comment raises a question about Spread. Does Piercing apply to Spread and Burst Damage? No other Effects apply to other Effects, is Piercing an exception?

[Sorry about all the brackets, btw.]

This makes the Spread Effect’s relationship with Damage Resistance very interesting. It means a Muzzled High Capacity Recoil-Compensated Ported Advanced Combat Shotgun (Damage 8 phys, Fire Rate 7) can do a maximum 120 Damage to an unarmoured Gary [by rolling all 15 Effects.]
15 initial Damage + 15 Spread Effects * [15/2, round down] = 120

but the same shot would only do 5 Damage to a Mirelurk Queen
[15 Dmg - 10 DR] + 15*[7 Dmg - 10 DR] = 5

Now, if the attacker has the Shotgun Surgeon Perk (Piercing +1), then those 15 Effects cancel out 15 DR on the initial attack, but does that Piercing apply to the Spread Effects?

If Piercing applies, the Mirelurk Queen takes all 120 Damage:
[15 Dmg - (10 DR - 15 Piercing)] + 15*[7 Dmg - (10 DR - 15 Piercing)] = 120

If Piercing does not apply to Spread, she only takes 15 Damage
[15 Dmg - (10 DR - 15 Piercing)] + 15*[7 Dmg - 10 DR] = 15

*I know the odds of rolling all 15 Effects is over 1 in 14 million, and that some of the Spread Effects would most likely hit the Mirelurk Queen’s face which is phys DR 5 not 10, but this is a thought experiment

It would be a headache if you were always rolling 7 Effects. With a regular Flamer, even adding all 4 ammo with Fire Rate, you roll an average of 2 Effects per attack. And then only if you hit. I think that’s very manageable.

Even a maxed-out Flamer (a Vaporizing Max Capacity Napalmer Flamer [Dmg 5 Fire Rate 6] if you were wondering. Needing no crafting perks or rare materials to upgrade!???) still only rolls an average of 4 Effects per attack. But yeah, the day that super weapon rolls 11 Effects, you’ve got some serious accounting to do.

The first difference is that A!C doesn’t have multiple hit locations, and thus no Spread effect. The second difference is that Fallout tracks individual shots of ammunition because scarcity of ammunition is more of a factor in Fallout than in other games where we treat ammunition more abstractly.

Piercing applies to all Damage Reduction which is applied during an attack.

How does piercing work? Let’s say I have 6 combat dice I roll 3 ones so 3 base dmg. And I roll 3 effects. I reduce dmg rs by 3. However if the target has an Ac of 2 does the third effect count as one dmg? Equaling 4 total dmg after 2 armor was reduced?

Effects already count as one damage. So in your example, you rolled 6 damage and 3 Piercing. A target with 2 Damage Resistance would take the full 6 damage.

You have to remember a simple rule :
Each effect rolled (5 or 6 on a normal d6) means : 1 damage + 1 effect.

So even if the effect is useless (like in your example 3 precision effects but only 2 DR), it still does 1 damage as normal. The third effect is just useless and doesn’t count.

So the target will suffer 6 damage (because of the reduced DR).