Defense

Every knight and monster carries some amount of defense against each damage type. Defense reduces the amount of damage received in an attack. For large attacks, the net damage incurred by the target is simply the gross damage inflicted by the attacker, minus the defense of the target. For smaller attacks, the relationship between net and gross damage is more complicated and not yet completely understood by the players of Spiral Knights.

Knight Defense

A knight's defenses are primarily determined by his (or her) armor. Based on measurements of 5-star armors, in Lockdown at depth 25, it seems that armor can provide five distinct levels of defense:

• "Base'" defense is the lowest amount — for example, the piercing defense on Skolver Coat. A full set (both pieces) of base defense armor has been measured at 125 defense points.
• "Class" defense is the second most common amount of defense — for example, the normal defense on Skolver Coat. A full set of class armor has been measured at 142.
• "Special" defense is seen on defensive armor sets — for example, the piercing defense on Royal Jelly Mail. A full set has been measured at 150.
• "Plate" defense can be seen in the normal defense of Volcanic Plate Mail, for example. It has been measured at 201 for a full set.
• "Heavy plate" defense can be found only on the Ancient Plate Mail/Helm. It has been measured at 301 for a full set.

The numbers are different for other depths and other star rankings, but the ratios remain representative. In addition to armor, there are several other sources of defense for knights:

• 5-star defense trinkets have been measured at 32 for a pair of trinkets at depth 25.
• Defense from unique variants have been measured at 52 for a double max at depth 25.
• Battle sprite perks are equal to UVs.

In Lockdown, all knights have a minimum amount of defense for each damage type. Defenses below this amount gets increased to said limit. For Tier 3 Lockdown, this is around 100 defense. For Tier 2, it's around 42.

Monster Defense

Monster defenses increase with depth. For each depth, there is a fixed "base defense value". This value is the difference between no defense (lost souls and howlitzer heads) and weak defense (for example, elemental damage against undead). This value is also the difference between weak defense and moderate defense (for example, shadow against constructs). Strong defense (for example, piercing against slimes) is not yet fully understood.

Here are some measured defense numbers. They are not exact, as the actual amounts are not integers. Instead, they are displayed as minimum for the first depth and a maximum for the last depth of a stratum.

Almost all monsters carry moderate defense against normal and one other damage type, weak defense against one damage type, and strong defense against one damage type. These types are determined entirely by the monster's family. However, there are a few exceptions. Oilers that are lit on fire get their elemental defense increased to strong defense. Lord Vanaduke does not belong to any family, and he has his own custom defenses: 180 normal, 150 piercing, 200 elemental, and 200 shadow. His mask has 150 normal and 200 piercing, elemental, and shadow defense.

Defenses can vary further depending on buffs and debuffs from poison, yesmen, danger rooms, etc.

Large Attacks

When the gross damage inflicted in an attack is greater than twice the defense of the target, the net damage incurred by the target is simply their difference:

net damage = gross damage - defense.

When there is more than one damage type on a weapon, each damage type is treated independently, to produce a net damage value. Then the net damage values are added up, for a total net damage.

For example, suppose that you find yourself on a Clockworks level where the standard monster defense value is 65. So a beast has 130 normal defense, 65 piercing defense, some large amount of elemental defense, and 130 shadow defense.

• Your normal sword does 400 gross damage, for net damage of 400 - 130 = 270 against the beast.
• Your piercing sword does 400 gross damage, for net damage of 400 - 65 = 335.
• Your normal+shadow sword does 550 gross damage, evenly split between its two damage types. The net damage is therefore (275 - 130) + (275 - 130) = 145 + 145 = 290.

Small Attacks

The relationship is more complicated when gross damage is less than twice the defense. We can be certain that

net damage < gross damage / 2,

but we do not understand much more than that. The practical effect of defense seems to diminish as the defense approaches gross damage.

Difficulty Setting Notes

While the exact influence is unknown, the Difficulty setting does influence defense values.

On normal difficulty, a knight can select incorrect armor and still have a non-zero defense against monster attacks. This is thought to explain the "base" defense observed in lockdown.

On elite difficulty, knights can select armor such that they achieve a 0 defense value.

References

This article is a synthesis of various player research projects, including:

• Private Training Hall measurements
• Damage measurements against Lost Souls, which have no defense
• Damage measurements against Howlitzer Heads, which have no defense
• Lockdown defense measurements
• The thread about the creation of this page, which holds further links
• Shankle damage against shields, which identifies shield HP values and identifies how armor is influenced with difficulty