Explosion math request.


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I had some questions that I hoped others could help me out with the math on. I’m at work and can’t do it myself right now, and in some cases don’t have access to the book to do so anyway. The questions are concerning the weapon quality explode. Please presume heavy weapons for the questions not grenades or other options.

1, how many targets must you hit on average to deal equivalent or greater damage with an unwieldy explode weapon in comparison to a comparable single target weapon, either as single shots or full attacking. Single target weapons have higher damage but excluding special abilities even a successful save deals half damage, whereas a missed shot deals nothing.

2, is it generally an advantage to use deadly aim with this weapon? I know that in most cases the penalty to hit is worse than the bonus damage but with explode even on a save half that damage goes through. So making someone 10% more likely to save but still take half, and half the extra damage, seems like it would make the feat generally useful.

3, how hard is it to keep up with the save curve shown in alien archive? It should be roughly the same as the spell save curve. And so long as you’re willing to accept slightly lower damage less important to keep maxed. Unless I’m miss remembering something lower dex mod is only -2.5% damage per 1 instead of -5%.

Thank you in advance, and please ask if I wasn’t clear on what I’m trying to check. I had to post this in a bit of a hurry.


It depends on how you interpret Unwieldy, and who's wielding it. NPC EAC/KAC roughly correlates with 10+3L/4, which is non-Soldier/Solarian BAB, so players get an edge while leveling provided they invest in things like stat buffs for their accuracy stat, etc. Reflex saves are faster - an NPC Combatant starts with a save of L+2 and has only degraded to L+1 at level 20! If you interpret Unwieldy as being totally unusable in a full attack, Soldiers and Solarians should not use it - they're better off attacking AC multiple times; if you interpret it as the weapon can't fire more than once in a full attack, then one with enough arms to full attack with 3 different ones (Skittermanders, or any of the 4-armed races with a pair of cyberarms added onto their spine) becomes more compelling. For a class that was never planning on full attacking anyway, like an Envoy, the concern is just the number of feats you'll have to burn to get there - Mechanics especially are very, very good with energy explodes unwieldy guns.

Note that a problem with explodes, which is only emphasized by the unwieldy question, is that the DC on the save suffers penalties but does not enjoy bonuses - so you can use Weapon Focus and Far Shot to totally negate your penalty for shooting out 1 range increment, but the DC on the save out there will be at -1, as Far Shot helps but Weapon Focus does not. This means anyone trying to use Explodes either needs to avoid penalties entirely, or has to hope their target lacks Evasion, and gun for as many penalties that provide something worthwhile as possible.

Here is the math on the primary explodes unwieldy guns of interest; I have left out grenades and grenade arrows due to their staggeringly high cost.

Plasma and Shock Cannons:

Shock L06 D06.5 R040 E10
Plasma L08 D11.0 R100 E5, Critical Burn 4.5
Shock L10 D13.0 R040 E15
Plasma L14 D22.0 R100 E5, Critical Burn 9
Shock L16 D32.5 R040 E20
Plasma L16 D33.0 R100 E5, Critical Burn 13.5
Plasma L20 D44.0 R100 E10, Critical Burn 18
Shock L20 D45.5 R040 E20


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quindraco wrote:
NPC EAC/KAC roughly correlates with 10+3L/4, which is non-Soldier/Solarian BAB, so players get an edge while leveling provided they invest in things like stat buffs for their accuracy stat, etc.

I think this logic is flawed.

A CR 1 combatant has EAC 11; KAC 13.
A CR 20 combatant has EAC 35; KAC 37
A CR 25 combatant has EAC 42; KAC 44

I would use approximate enemy EAC as 10 + 1.6*L; And KAC as 12 + 1.6*L.

To maintain the same average accuracy from 1 to 20. A soldier needs to increase his to hit bonus by 24. He gets 19 BAB, 2 to 4 (depending on starting stat) from attribute level increases, 3 from a item based enhancements. Which means average hit rate should stay about the same from level 1 to 20 if you're a an optimized full BAB class.

It is slightly worse for explosive weapons though. The average combatants reflex save increased by 18 over 19 levels. And save target DC only increases by 10+Stat mod change or 15 if fully optimized. So no matter what you do, the chance your opponent will save for half damage increases over time.

A core belief in Starfinder seems to be every character will absolutely maximizes anything he does, if he doesn't he can expect to get progressively worse at it as he levels up.


Pathfinder Starfinder Adventure Path, Starfinder Roleplaying Game Subscriber
Maezer wrote:
... A core belief in Starfinder seems to be every character will absolutely maximizes anything he does, if he doesn't he can expect to get progressively worse at it as he levels up.

Something i have been concerned about as well. i have only theory crafted so far so i dont want to put too much stock in this thought just yet but it is intensely worrying.


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Pathfinder Starfinder Society Roleplaying Guild Subscriber

Because I love doing math and spreadsheets, I ran a comparison of a Bombard Soldier (their 5th level power lets them apply STR mod to explosive weapons if they use a special full action) using deadly aim vs. an Alien Archive combatant NPC, ie. one with a good Reflex mod. I then compared the expected damage per round vs. a heavy weapons sharpshooter soldier (with reaction cannon).

Here's some rules of thumb:
@6th level when you get your first explode weapon, just catching one enemy in your explosion more or less equals the full attack of a soldier with a reaction cannon! Nice! Sadly this won't be true ever again.
@7th through 12th levels, two enemies caught in the explosion allows you to exceed the damage of a reaction cannon full attack by 10-40%.
@13th through 20th levels, you need at least three enemies caught in the explosion to exceed the full attack damage of the reaction cannon soldier.

When not able to make full attacks, the rule of thumb is a bit simpler:
You need at least two enemies caught in your explosion to exceed the single attack damage of a reaction cannon soldier.

To answer your other Qs:
2) Yes, it is always advantageous to deadly aim with explode weapons, despite the hit to their save DC. You gain 1-2 average damage per round, which is small but consistently beneficial.
3) You will fall behind the save DC curve even when doing your best to max out the save DC, but this is true for Technomancers/Mystics as well! Keeping it as high as possible is always going to be worthwhile for you.

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