Damage Mechanics ยท Worked example
Damage Saturation Explained: Why Torpedoes Hurt a Destroyer Less Than a Battleship
It is one of the most common confusions in Legends. The same torpedo lands on a Tier X battleship for 20,000 damage, then lands on a Tier VIII destroyer for 13,000. The natural conclusion is that the destroyer must have some hidden torpedo resistance. It does not. The answer is a mechanic called damage saturation, and once you understand it, a lot of strange damage numbers stop being strange.
First, kill the obvious theory
If a destroyer were soaking torpedo damage through a stat, that stat would be its torpedo damage reduction, the same value battleships get from their torpedo bulges. GamingDiver tracks that figure for every ship and shows it on the ship page under Survivability as Torp Reduction.
Pull up Marceau, the Tier VIII French destroyer from the example above. Her torpedo reduction reads 0%. Compare that to Bismarck at 22% or Yamato at 55%. Destroyers carry no torpedo bulge, so they get no torpedo damage reduction at all. The stat answer to "how much torpedo reduction does this destroyer have" is simply zero, every time. That is a dead end, which means the 13,000 figure is being produced by something that is not a ship stat.
A ship is not one health bar
The health number you see in port is a total. Underneath it, every ship is split into sections: the bow, the stern, the superstructure, the midship (casemate), the hull, and the citadel. Each section has a listed HP, and behind that listed HP sits a pool of damage the section can take at full value. The pool is twice the section's listed HP. A hit that penetrates a section drains that section's pool.
Marceau's bow lists 2,900 HP, so its pool is 5,800. Yamato's bow lists 7,200, so its pool is 14,400. A battleship's sections are big. A destroyer's are small.
The three levels of damage
| Section state | Incoming penetrating damage |
|---|---|
| Pool has anything left | Full value, and the pool drains by the same amount |
| Section pool empty | Exactly half |
| Section pool and the ship-wide hull pool both empty | Much less again, and rare |
The hit that empties a pool is split: it deals full damage for whatever was left in the pool, and half for the rest. A hit is never simply capped at the HP a section has left.
The third level comes from a second, ship-wide pool tied to the hull. Hits on the bow, stern and superstructure drain it at their full value, even when the hit itself was halved. That pool is twice the hull section's listed HP, and fewer than one ship in a hundred ever empties it, mostly destroyers near the end of their life. When it does run dry, hits on empty sections fall to a small fraction of their listed damage.
What never saturates
- Citadel hits. A citadel hit deals full damage however wrecked the ship is, which is why a citadel on an already-battered cruiser can still delete it.
- A destroyer's midship. Like the citadel, it never runs out. Hits amidships on a destroyer always deal full damage.
- Overpenetrations. An overpen deals a tenth of the shell's damage and neither drains nor cares about the pools.
- Torpedoes on a battleship's or cruiser's belt. They count against the citadel. Torpedo protection cuts them, but they never saturate. A torpedo on the bow or stern does saturate.
Why destroyers live in saturation
Saturation hits destroyers harder than anything else for one simple reason: the sections are tiny. A single torpedo is bigger than a destroyer's whole bow pool.
Here is a Minegumo putting three torpedoes into a Marceau's bow, one after another, in under two seconds. The Marceau has 23,700 HP and 0% torpedo protection. One Minegumo torpedo is worth 19,567 against her at full damage, so two should sink her with room to spare. They do not:
| Torpedo | Damage | What happened |
|---|---|---|
| 1 | 12,681 | The bow's 5,800 pool emptied. That part landed at full damage; the rest of the torpedo landed at half. |
| 2 | 8,855 | The bow was already empty, so half damage. The ship-wide hull pool ran out during this hit. |
| 3 | 1,935 | Both pools empty: about a tenth of a full hit. |
The Marceau limped away on 166 HP. Without saturation, the second torpedo sinks her.
A battleship behaves differently only because its sections are huge. The same kind of spread into a Yamato's bow lands at full value until that 14,400 pool runs out, and torpedoes that reach her belt never saturate at all. That, not a hidden resistance stat, is the gap between the 20,000 and the 13,000.
Torpedoes are not reduced at the tips
A common belief is that torpedoes hitting the bow or stern are cut to about a third. They are not. A torpedo on the bow or stern deals its full listed damage as long as that section has pool left. Torpedo protection only reduces hits on the belt, and the tips lose value only through saturation.
What to do with this
- Spread your torpedoes across the hull. A full spread into one section of a destroyer wastes most of the salvo to saturation. Torpedoes walking down the length of a target pay out far better than torpedoes stacked on the same spot.
- Aim torpedoes amidships on destroyers. A destroyer's midship never saturates, so a torpedo there always pays in full. Its bow and stern pools are small enough for one torpedo to empty.
- Finish battered destroyers with guns on a fresh section. If a destroyer's bow has already soaked a torpedo, more torpedoes there land at half or less. A few HE shells amidships, or a single torpedo there, is more reliable than a full spread into the drained end.
- Do not read "0% Torp Reduction" as "torpedoes do full damage." That stat only describes torpedo protection. Saturation is a separate mechanic that no ship page can show as a number, because it depends on how damaged the target already is.
Ship figures: Marceau Tier VIII destroyer, 23,700 HP, bow 2,900 HP, 0% torpedo protection; Minegumo torpedo 19,567 at full damage against her; Yamato bow 7,200 HP. Torpedo protection values for Bismarck (22%) and Yamato (55%) are from each ship's survivability stats.