Defense

Defense is a player statistic that determines how much damage can be taken per hit. Defense can be increased by wearing armor and accessories, and temporarily boosted by various buffs.

• In Classic Mode, incoming damage is reduced by half of defense rounded up.
• In Expert Mode, incoming damage is reduced by 75% of defense rounded up.
• In Master Mode, incoming damage is reduced by 100% of defense.

No hit can be reduced below 1 damage (with the exception of a player whose multiplayer ally is wearing a Paladin's Shield).

Some forms of damage are impossible to reduce through defense. Damage from health-draining debuffs like Cursed Inferno or drowning in water are not reduced by defense. Damage taken from lava, however, can be reduced through defense.

Mechanics

Defense gives a flat reduction in damage, i.e. damage is reduced by a fixed amount per hit (as opposed to a multiplicative damage reduction, which would reduce damage by a percentage).

Normal Mode formula

The formula is: net damage = attack damage - (defense * 0.5)

For example:

• With 20 defense, a 40 damage attack is reduced by 10, resulting in 30 damage taken: 40 - (20 * 0.5) = 30
• With 30 defense, a 40 damage attack is reduced by 15, resulting in 25 damage taken: 40 - (30 * 0.5) = 25

Expert Mode formula

In expert mode, the formula is: net damage = attack damage - (defense * 0.75)

For example:

• With 20 defense, a 40 damage attack is reduced by 15, resulting in 25 damage taken: 40 - (20 * 0.75) = 25
• With 30 defense, a 40 damage attack is reduced by 23, resulting in 17 damage taken: 40 - (30 * 0.75) = 17

Note that in Expert mode only the player's defense follows the formula. Enemies will still take the same amount of damage as in normal mode.

Master Mode formula

In master mode, the formula is:net damage = attack damage - defense

For example:

• With 20 defense, a 40 damage attack is reduced by 20, resulting in 20 damage taken: 40 - 20 = 20
• With 30 defense, a 40 damage attack is reduced by 30, resulting in 10 damage taken: 40 - 30 = 10

Enemies

Enemies have a defense statistic just like players do, but they do not gain more protection from defense in Expert Mode or Master Mode. Enemies will always reduce incoming damage by 50% of their defense regardless of difficulty: net damage = attack damage - (defense * 0.5)

Examples:

Weapon	Green Slime 0 defense	Chaos Elemental 30 defense	Paladin 50 defense	Sharkron 100 defense
Gold Broadsword 13 damage	13	1 (-2)	1 (-12)	1 (-37)
Meowmere 200 damage	200	185	175	150

Altering defense

Armor and Accessories

A player's defense score can be increased by equipping armor and accessories. Armor usually consists of three items, granting an additional bonus, the Set Bonus, which may increase the defense score further, if all three pieces match. Some accessories grant direct defense boosts (see the following table), but all accessories can also be reforged to a maximum of +4 defense per accessory.

See armor for detailed defense information about every piece of armor.

The following accessories increase the player's defense:

Item	Accessory Defense
Shackle	1
Cobalt Shield	1
Obsidian Skull	1
Shield of Cthulhu	2
Obsidian Shield	2
Moon Charm	3 (only during the night)
Moon Shell	3 (only during the night)
Moon Stone	4 (only during the night)
Sun Stone	4 (only during the day)
Celestial Stone	4
Ankh Shield	4
Paladin's Shield	6
Frozen Shield	6
Celestial Shell	4 (during the day) 7 (during the night)
Flesh Knuckles	8
Berserker's Glove	8
Hero Shield	10
Frozen Turtle Shell	0 until below 50% health when it reduces total damage by 25%   30 (when below 25% health)

Buffs and Debuffs

Buffs and debuffs can temporarily alter a player's or an enemy's defense. Currently, there is no buff increasing enemies' defense. A player's defense cannot be reduced to fall below 0.

Buff / Debuff	Temporary Defense
Well Fed	2
Plenty Satisfied	3
Exquisitely Stuffed	4
The Bast Defense	5
Dryad's Blessing	8
Ironskin	8
Tipsy	-4
Weak	-4
Ichor	-20 ( -15)
Betsy's Curse	-40
Broken Armor	-50%

Damage reduction boosts

All damage reduction boosts (except Warmth Potion) affect damage taken after defense. Also, Solar Blaze, Beetle Endurance, Warmth and Paladin's Shield calculate damage multiplicative with each other and other effects calculate additive. So firstly the raw damage is decreased by the Banner's effect (25% reduction for Normal mode and 50% for Expert and Master) and Warmth Potion (30% reduction from cold source), then the remaining damage is reduced by defense (0.5 per defense for Normal mode, 0.75 for Expert and 1 for Master), the remaining damage is then reduced by all additive damage reduction, then by Beetle and Solar Flare armor's buff, finally by Paladin's shield. (also, each step will round down the damage value but the value cannot be less than 1)

Buff	Source	Damage reduction bonus
Solar Blaze	Solar Flare armor	20%
Beetle Endurance	Beetle armor	15% / 30% / 45%
Paladin's Shield	Paladin's Shield (when worn by another player on the team)	25% (only active when the wearer is above 25% health)
Endurance	Endurance Potion	10%
Ice Barrier	Frozen Turtle Shell, Frozen Shield	25% (when below 50% health)   0
Warmth	Warmth Potion	30% (reduces damage only from cold-themed enemies)
Item	Source	Damage reduction bonus
Chlorophyte Mask(with whole set)	Crafting	5%
Turtle armor	Crafting	15%
Solar Flare armor	Crafting	12%
Worm Scarf	Treasure Bag (Eater of Worlds)	17%

For example, in a master world, a cold-themed enemy somehow will deal 2000 damage to a player, the player wears a full set of Solar Flare armor (with its buff), a Worm Scarf, a Frozen Turtle Shell (with its buff on), with buff of Endurance, Warmth, a banner of that enemy, a teammate with Paladin's Shield and 140 defense.

1. The banner reduces the damage by half, so 1000;
2. The Warmth potion reduces it by 30%, so 700;
3. The defense reduces it by 140, so 560;
4. The Worm Scarf (17%), Endurance (10%), Solar Flare armor (12%) and Frozen Turtle Shell (25%) reduce damage additively, so they reduce it by 64%, so 201.6, round down, 201;
5. Solar Flare armor's buff reduces it by 20%, so 160.8, round down, 160;
6. A teammate's shield will reduce it by 25%, so player will take 120 damage.
7. The teammate will take 40 damage, and it will be further reduced by that player's status (banner and warmth will not take effect though)

Armor Penetration

Armor penetration is hidden statistic that ignores portion of enemies defense. For instance, a Pixie normally has 20 defense. If the player has Shark Tooth/Stinger Necklace, then the Pixie will be taken to have 15 defense instead.

Source	Armor penetration bonus
Shark Tooth Necklace	5
Stinger Necklace	5
Sharpening Station	12 (for melee weapons only)
Blade Staff	25
Crystal Vile Shard	10
Nettle Burst	10
Wasp Gun	10
Star Cloak and its upgrades.	25
Arkhalis	20

Max defense

The highest possible defense uses the following setup:

 Desktop version and  Mobile version

• Armor – 82 defense in total
  • Solar Flare Helmet or Hallowed Mask – 24 defense
  • Solar Flare Breastplate – 34 defense
  • Valhalla Knight's Greaves – 24 defense
• Accessories (at night) – 54 / 64 / 77 defense in total
  • Hero Shield - 10 defense
  • Flesh Knuckles – 8 defense
  • Berserker's Glove - 8 defense
  • Celestial Shell – 7 defense (at night when not submerged)
  • Frozen Shield – 6 defense
  • Paladin's Shield - 6 defense
  • Ankh Shield - 4 defense
  • Warding modifiers on all accessories – 20 / 24 / 28 defense
• Buffs – 25 defense in total
  • Ironskin – 8 defense
  • Exquisitely Stuffed – 4 defense
  • Dryad's Blessing – 8 defense
  • The Bast Defense – 5 defense
• Guarding with the Brand of the Inferno or Sergeant United Shield – 20 defense

Therefore, the maximum defense is: 82 + 59 + 25 + 20 = 186 / 82 + 69 + 25 + 20 = 196 / 82 + 77 + 25 + 20 = 204.

 Console version

• Armor – 79 defense in total
  • Chlorophyte Mask – 25 defense
  • Solar Flare Breastplate – 34 defense
  • Valhalla Knight's Greaves, Solar Flare Leggings, or Vortex Leggings – 20 defense
• Accessories (at night) – 48 / 56 defense in total
  • Flesh Knuckles – 7 defense
  • Celestial Shell – 7 defense
  • Paladin's Shield – 6 defense
  • Two out (all) of Ankh Shield, Moon Stone, Celestial Stone – 8 / 12 defense
  • Warding modifiers on all accessories – 20 / 24 defense
• Buffs – 18 defense in total
  • Ironskin – 8 defense
  • Well Fed – 2 defense
  • Dryad's Blessing – 8 defense
• Guarding with the Brand of the Inferno – 20 defense
• Additionally, if a player is traveling at top speed in a Mechanical Cart, they can reach a defense boost of 7.

Therefore, the maximum defense is: 79 + 48 + 18 + 20 = 165 / 79 + 56 + 18 + 20 + 7 = 180.

 Old-gen console version and  3DS version

• Armor - 76 defense in total
  • Dragon Mask - 26 defense
  • Beetle Shell - 32 defense
  • Beetle Leggings 18 defense
• Accessories - 42 defense in total
  • Paladin's Shield – 6 defense
  • Ankh Shield - 4 defense
  • Moon Stone (at night)/Sun Stone (at day) - 4 defense
  • Frozen Turtle Shell (at low health) - 30 defense
  • Celestial Stone - 4 defense
  • Warding modifiers on all accessories – 20 defense
• Buffs - 10 defense in total
  • Ironskin – 8 defense
  • Well Fed – 2 defense

Therefore, the maximum defense is: 76 + 42 + 10 = 128

Damage reduction

Damage reduction is calculated after defense.

The highest damage reduction possible is 73.6% (or 81.52% against cold-themed enemies), using the following setup:

 Desktop version,  Console version, and  Mobile version

• Armor (multiplicative)
  • Beetle armor with shell – 45% reduction
  • Warmth Potion - 30% reduction against cold-themed enemies
• Accessories and Potions (additive)
  • Frozen Turtle Shell – 25% reduction
  • Worm Scarf – 17% reduction
  • Endurance Potion – 10% reduction
  • If Paladin's Shield buff is on, it can reduce additional 25% damage after defense.

Therefore, the maximum damage reduction is: (1 - 0.45) * (1 - (0.25 + 0.17 + 0.1)) = 0.264 = 26.4% damage taken = 73.6%

The maximum damage reduction against cold-themed enemies is: (1 - 0.45) * (1 - 0.3) * (1 - (0.25 + 0.17 + 0.1)) = 0.1848 = 18.48% damage taken = 81.52% (note that the Warmth Potion is calculated before defense).

 Old-gen console version

• Armor (multiplicative)
  • Beetle armor with shell – 45% reduction
• Accessories and Potions (additive)
  • Endurance Potion – 10% reduction
  • Warmth Potion - 30% reduction against cold-themed enemies
  • This does not include the Paladin's Shield buff, since its damage reduction occurs before defense, and all others occur after defense.

Therefore, the maximum damage reduction is:(1 - 0.45) * (1 - 0.1) = 0.495 = 49.5% damage taken = 50.5%

The maximum damage reduction against cold-themed enemies is: (1 - 0.45) * (1 - (0.1 + 0.3)) = 0.33 = 33% damage taken = 66%

 3DS version

• Armor (multiplicative)
  • Beetle armor with shell – 45% reduction
• Accessories and Potions (additive)
  • Endurance Potion – 10% reduction
  • This does not include the Paladin's Shield buff, since its damage reduction occurs before defense, and all others occur after defense.

Therefore, the maximum damage reduction is: (1 - 0.45) * (1 - 0.1) = 0.495 = 49.5% damage taken = 50.5%

Trivia

• Although not possible in-game, if a piece of armor were to gain a modifier, it would apply the effects just like an accessory would. For example, a set of Warding modified armor would add 12 defense total; each piece adds 4 defense to the total.
• Damage dealt by enemies is doubled in Expert mode and tripled in Master Mode compared to normal mode. This means that despite the increase in damage reduction from defense in those modes, defense is still generally less effective than in normal mode.
• If the player somehow has negative defense, they will take more damage according to the damage taken added with half / three quarter /full amount the defense.