Defense

is one of the core player statistics. It determines how much Damage reduction the player has. The more a player has, the less damage is taken from attacks. goes below 0, but doesn't have any effect.

Defense does not reduce ; that is reduced by.

Mechanics
The more the player has, the less bonus damage reduction the player will have.

The formula for damage reduction is

$$\frac{Def}{Def + 100}$$ damage reduction. For example, if Defense is 200, the formula is

$$\frac{200}{200+100} = \frac{200}{300}$$ or ~67% damage reduction, meaning with 200, the player takes 33% of the damage from monsters that would normally be taken with 0 defense.

This leads to a misconception that higher is useless because the damage reduction only goes up slightly. This is incorrect, for as the difference from 0% to 50% damage reduction may seem more substantial than the jump from 90% to 95%, both are equal in that they double EHP (Effective Health Points) (100-200 vs 1000–2000)

Effective Health
(EHP) is the amount of damage enemies need to deal to the player to kill them when is factored in. If one has 100 and 200, they will be able to take 300 damage before dying, as shown below.

The formula for EHP is

$$HP \times \frac{Def + 100}{100}$$ .

For example, if is 200 and  is 100, the formula is:

$$100 \times \frac{200 + 100}{100}$$ or

$$100 \times \frac{300}{100}$$ or

$$100 \times 3$$ or

300 EHP, meaning with 100 and 200, the player can take as much damage without dying as someone who has 300  and 0  could.

EHP is a useful metric for calculating which items are better than others in allowing the player to survive attacks.

EHP does not factor in attacks, which are affected by.

Increasing Base Defense
Players do not have any base by default. It can be increased by:
 * Leveling
 * The Forbidden Defense upgrade in Wither Essence shop.
 * The Forbidden Defense upgrade in Wither Essence shop.

Increasing Bonus Defense
There are several ways to gain additional bonus. They include, but are not limited to:
 * Equipping most types of Armor
 * Holding certain weapons (Golem Sword, Earth Shard, Wither Cloak Sword, Adaptive Blade (When Tank in dungeons), or Astraea)
 * Using Accessories (ex: Gravity Talisman)
 * Using on Armor
 * Equipping certain Pets
 * Reforging items to certain Reforges (ex: Titanic Reforge)
 * Drinking the Resistance Potion
 * Abilities such as Pigman Sword's

<!--== Achieving Max Defense == To achieve max defense possible in game, a player needs to do the following:


 * Achieve Catacombs 50, which boosts dungeon item stats inside dungeons by 515%.
 * Achieve Mining 60, turn in all 220 Fairy Souls, and get Forbidden Defense V for 163 base defense. Base defense can then be increased by another 50 by getting Defense Essence V from the Undead Essence shop.
 * Wear a full set of Recombobulated Absolutely Perfect Armor (Tier XII) with Protection VII with 10 Hot Potato Books and 5 Fuming Potato Books. This set gives 1871 defense outside dungeons. While inside dungeons, this is boosted by 515%, for a grand total of 11506.65 defense from the armor alone.
 * Use an Astraea, which gives 260 defense inside dungeons. Once again, this is boosted inside dungeons by 515%, meaning from the sword you will gain 1599 defense with this sword. Also, right before this you can use the Pigman Sword's ability for another 300 defense. Use a Bulky Stone to apply the Bulky reforge to both the Astrea and Pigman sword, which grants additional defense
 * A Resistance 8 Potion can be drunk inside a dungeon for 66 defense.
 * in total so far, we are at 13684.65 defense.
 * A Tank level 50 will give an instant buff of defense by 100 for our new total to be 13784.65. In addition, tank 50 buffs all defense by 35%. With the tank buff, our defense is now 18609.2775.
 * Putting Last Stand V on the perfect armor means whenever your health is below 40%, you will gain +100% defense. So we multiply our current defense by 2 and we get 37218.555 defense.
 * As our defense is extremely high, the best pet for us would be a turtle pet. 37218.555*1.2 = 44662.266 defense. Turtle pet also gives 100 defense as its base stat, which can then be copied onto the Astraea with Chimera V. The copied stats will get buffed inside dungeons. The turtle pet also buffs defense by 40 while near water. The total defense buff from turtle pet is 755. However, this defense is then increased by the Tank Class and by Last Stand. In total, the turtle pet buffs the defense by 2038.5, for a new total of 46700.766 defense.
 * Finally, 4 pieces of the Perfect reforge will increase total defense by 2% each, stacked multiplicatively. The final total max defense is 46700.766*1.02*1.02*1.02*1.02 = 50550.411
 * Although Blessings can increase that further, the blessing buffs are inconsistent. Therefore, 50,550.411 defense is generally considered the max defense you can have in the game. That is over 99.8% damage reduction.
 * With maxed-out skills (Farming, Fishing, Slayers, ect.), Growth VII, Fairy souls, Essence shop, and following the same steps as stated above, you can get a maxed-out health of 6,069 HP. If we assume Last Stand is activated our health has to be at a maximum of 2,427 HP (40%). Using the EHP formula we get a total of 1,229,275.5 EHP. Hypothetically if Last Stand was activated at 100% HP we could achieve 3,073,948.5 EHP.-->

Trivia

 * When the approaches infinity(i.e. having the maximum defense), the damage reduction approaches 100%.
 * However, the 100% is an estimated number, due to how Effective Health is calculated.
 * To truly get infinite Effective Health, the only way is to let the naturally regenerated Effective Health outclass the taken.

History
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