EPTThe siege tank has 70 atk base damage, with +5 to each upgrade, a 7.1% increase. A fully upgraded siege tank has a 21.4% atk increase, while a fully upgraded marine has a 50% atk increase. Does this means that a fully upgraded marine is stronger than a fully upgraded tank? Well, that depends. If the opponent has no defensive upgrades, then yes, otherwise no. You can nullify the marine upgrades by getting defensive upgrades, which is not the case for siege tanks. But how much can you reduce the siege tank damage?
Let's first look at how the siege tank deals damage. The formula for radial splash damage is: (Original Damage*Splash Modifier)-Armor]*(Damage Type)
Original damage is the attack from the siege tank. The splash modifier is where the unit is located with relation to the hit/target. The armor is the total armor of the unit being hit, and the damage type is the damage type of the siege tank. Siege tanks have explosive damage, meaning they deal 100% to large units, 75% to medium units, and 50% to small units.
How does the splash modifier work for radial splash damage? Here is how the damage is theoretically distributed, where the taget (T) deals 100% damage, the inner radius (R1) deals 50% damage and the outer radius (R2) deals 25% damage.
![[image loading]](https://i.imgur.com/pEROOmX.png)
Here is how the damage is distributed with a siege tank shooting at dragoons and zealots:
![[image loading]](https://i.imgur.com/QPZWjSQ.png)
![[image loading]](https://i.imgur.com/ngcsALN.png)
The damage distribution is not even. Units closer to the siege tanks are dealt more damage than the ones further away. Either way, the splash damage radius is similar to that of a storm.
In game, units wont be this clumped up. But to put a number on the damage dealt, the dragoons are dealt 550% of the original siege tank target damage, and the zealots are dealt 900/2 = 450%. Let's say an average damage dealt by a siege tank in a maxed vs maxed out fight is 250% (f.e 1x100%, 2x50% and 2x25% vs dragoons).
Let's get into the upgrades. Using the equation above to calculate radial splash damage, we get the following scenarios: This is the damage dealt to Dragoons Armor. Shields are similar, but start with default 0 armor instead of 1 armor and is often removed by EMP/voltures anyways. The damage to upgrade ratio is similar for zealots/hydra's, so let's skip those calculations.
0-0 Tank (70 Atk) vs 0-0-0 Dragoon (1 Arm)
T: (70*1-1) * 1 = 69 dmg
R1: (70*0.5-1) * 1 = 34 dmg
R2: (70*0.25-1) * 1 = 16.5 dmg
The average damage per shot dealt with no upgrades is 1x69 + 2x34 + 2x16.5 = 170 damage
1-0 Tank (75 Atk) vs 0-0-0 Dragoon (1 Arm).
T: (75*1-1) * 1 = 74 dmg (7.2% increase)
R1: (75*0.5-1) * 1 = 36.5 dmg (7.3% increase)
R2: (75*0.25-1) * 1 = 17.75 dmg (7.6% increase)
2-0 Tank (80 Atk) vs 0-0-0 Dragoon (1 Arm).
T: (80*1-1) * 1 = 79 dmg (14.5% increase)
R1: (80*0.5-1) * 1 = 39 dmg (14.7% increase)
R2: (80*0.25-1) * 1 = 19 dmg (15.2% increase)
3-0 Tank (85 Atk) vs 0-0-0 Dragoon (1 Arm)
T: (85*1-1) * 1 = 84 dmg (21.7% increase)
R1: (85*0.5-1) * 1 = 41.5 dmg (22.1% increase)
R2: (85*0.25-1) * 1 = 20.25 dmg (22.7% increase)
The average damage per shot dealt with 3-0 is 1x84 + 2x41.5 + 2x20.25 = 207.5 damage (22% increase). The damage for all areas is increased by around 7% for each upgrade when the Dragoons have no upgrades at all.
What happens with upgrades? Let's assume siege tank and dragoon upgrades are equal to each other through out the game.
1-0 Tank (75 Atk) vs 0-1-0 Dragoon (2 Arm).
T: (75*1-2) * 1 = 73 dmg (5.8% increase)
R1: (75*0.5-2) * 1 = 35.5 dmg (4.4% increase)
R2: (75*0.25-2) * 1 = 16.75 dmg (1.5% increase)
2-0 Tank (80 Atk) vs 0-2-0 Dragoon (3 Arm).
T: (80*1-3) * 1 = 77 dmg (11.6% increase)
R1: (80*0.5-3) * 1 = 37 dmg (8.8% increase)
R2: (80*0.25-3) * 1 = 17 dmg (3% increase)
3-0 Tank (85 Atk) vs 0-3-0 Dragoon (4 Arm)
T: (85*1-4) * 1 = 81 dmg (17.4% increase)
R1: (85*0.5-4) * 1 = 38.5 dmg (13.2% increase)
R2: (85*0.25-4) * 1 = 17.25 dmg (4.5% increase)
The average damage per shot dealt with maxed upgrades are 1x81 + 2x38.5 + 2x17.25 = 192.5 damage (13.2% increase). With equal upgrades, the damage is increased by about 6% for T, 4% for R1 and 1.5% for R2 for each upgrade increase.
This means, that the increased damage from siege tank upgrades is removed by 80% in R2, 40% in R1 and 20% at T.
According to our scenario, 41% of the increased damage from upgrades are removed, which is 7.2% of the total damage dealt (192.5 instead of 207.5 per shot). Comparatively, siege tank armor upgrades neglect 100% of the increase attack upgrade for zealots, and 50% for dragoons. If no splash damage is dealt, only 20% of the siege upgrade damage is neglected (3 armor vs 15 attack at full upgrades).
An interesting notation for mech upgrades is how the Goliath has 2x10 anti air damage and gains +4 (20% increase) for each upgrade, making it the highest increase in the game? As a comparison, Zealots/Firebats have 2x8 damage and only gain +2 (12.5% increase) per upgrade. Voltures and Dragoons have 20 damage and gets +2 (10% increase).
What can we conclude from this? Well, fully upgraded siege tanks are pretty damn strong, but armor at least reduces an okay amount of the splash damage dealt in the outer regions, making it useful for larger army fights.
