What does "up to X damage" exactly mean?

When shooting, the game informs you the shot will do "up to" some number of damage, and sometimes it does a bit less. Does anyone know formulas and probabilities?

Also, I am seeing my Assault with Plasma Rifle "does up to 8 damage" while rifle itself should do 7. Maybe it's a Normal difficulty buff? Or is it because his nickname's "Psycho"? :-)

• I think the latter case happens sometimes when you shoot a flanked enemy. Commented Oct 22, 2012 at 9:32
• @Shadur pretty sure flanking only makes you more likely to hit (by removing the enemy's bonus to defense from cover) and crit, not the damage. Commented Oct 23, 2012 at 12:43
• @kotekzot I remember taking more damage then normal while being flanked tho,but can't remember if i did more damage when flanking Commented Oct 31, 2012 at 10:44
• @Lyrion were you taking extra damage on non-crits? Commented Oct 31, 2012 at 11:34
• @kotekzot Hmm, that might be it. Can't really say. Commented Oct 31, 2012 at 11:55

If base damage of the weapon as listed on info screen is 4 it means that non-critical hits will hit from 3 to 5 at random with 4 being the most probable. In such cases you will see "up to 5". It does not mean that you will always hit for 5 damage, you may hit for less. The number shown depends only on your weapon, nothing else seems to affect it. If the shot crits you can deal more than 5 damage.

• This seems reasonable! While I'll write down some probabilities, does anyone have conflicting experience? @Sterno did report some out-of-ordinary bonuses... Commented Oct 26, 2012 at 23:47
• I had little time to play lately, but @Muxecoid 's theory seems to hold - there is ±1 damage spread, and +50% critical bonus is applied after that. So a 9 damage Plasma can do a (9+1)*1.5 = 15 damage criticals. I'm gonna accept this answer after I find some more details and edit them in (or someone else provides them). Commented Oct 31, 2012 at 11:30

From my experience, up to X damages is the damage you would do from your weapon base damage plus your abilities if you don't shoot a cover. This should explain de +1 of your example. Note that you can always press F1 to see the soldier profile.

On top of this, you will have to addition the critical hits if any. Obviously, you can do less damage: hitting covers, damage dissemination due to distance (to be confirmed, but I think of shotguns for example), damage negation from the enemy (I know there is a perk like this for your heavies, so maybe aliens may have it too).

I tried to look for game mechanism details, but they don't seem to be available. However, probabilities are summed up in the "More Info" button when you are about to shoot. As far as a "normal difficulty buff" is concerned, I doubt there is one. But I don't have so much experience in various difficulties. EDIT: there may be a bonus depending on your game difficulty as suggested by the options described for the .ini file at this source.

• The only ability I know that increases base damage is Gunslinger for snipers, but that adds 2, not 1 to damage. Commented Oct 23, 2012 at 12:38
• I agree with Kotekzot. Can you list the abilities that you think might be increasing damage? I mean, my plasma rifle says "up to 10 damage" on an assault or support guy on Classic diffculty, even though base damage is 7 and critical damage is 10. Those classes have no "do +3 damage with plasma rifles" ability, and they have that damage listed whether they're rookies or seasoned vets. Perhaps it's a bug (or working as intended but unintuitive) and it's always listing critical damage there? Either that or every class has a hidden bonus. Commented Oct 23, 2012 at 13:28
• I could be wrong about passive abilities. Neverthless, the ini file shown in the link clearly show that all soldiers gets the same bonuses from the game difficulty modifier. I also do not know enough of the game to list the abilities, I also though of the Gunslinger. Not sure if elevation bonus adds damage.
– M'vy
Commented Oct 23, 2012 at 13:41
• @M'vy, this file is a godsend! Unrelatedly, Titan Armor has Properties[0]=eAP_DualWield... Y U remove dual wielding, Firaxis?!! :-) Commented Oct 23, 2012 at 14:09
• On topic - there are no iDamage bonuses for any difficulty for eChar_Soldier. Commented Oct 23, 2012 at 14:33