> For the complete documentation index, see [llms.txt](https://aincrad-legacy.gitbook.io/aincrad-legacy-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://aincrad-legacy.gitbook.io/aincrad-legacy-docs/combat-system/defenses.md).

# Defenses & Damage Reduction

Since attacks in Aincrad Legacy [rarely miss](/aincrad-legacy-docs/combat-system/no-miss-combat.md), surviving is about shrinking the damage that connects. Four defensive stats do that work, in two matched pairs: **DEF / MDEF** and **RES / MRES**.

## DEF and MDEF

**DEF** reduces physical damage, **MDEF** reduces Aura damage. Both use the same formula - the damage you take is multiplied by:

```
(4000 + DEF) / (4000 + DEF x 10)
```

Some comparison values:

| DEF or MDEF | Damage reduced |
| ----------- | -------------- |
| 200         | 30%            |
| 400         | 45%            |
| 800         | 60%            |
| 1600        | 72%            |

Every point keeps helping, but each one buys a little less than the last - there is no hard cap, just diminishing returns.

## RES and MRES

**RES** (physical) and **MRES** (Aura) are a second, rarer reduction layer with its own formula - damage is multiplied by:

```
(2000 + RES) / (2000 + RES x 8)
```

| RES or MRES | Damage reduced |
| ----------- | -------------- |
| 100         | 25%            |
| 333         | 50%            |
| 545         | 60%            |
| 1500        | 75%            |

RES/MRES applies **on top of** DEF/MDEF - the two layers multiply, so stacking both is far stronger than stacking either alone.

## Flat (soft) defense

Besides the percentage layers, a small **flat** reduction (grown mainly by VIT for physical, INT for Aura) is subtracted from incoming damage. The flat part applies **after** all percentage reductions, so it is never diluted by them - a real bonus for tanky builds against fast, weak hits.

## Piercing

Defense-piercing effects reduce your **reduction percentage**, not your raw DEF number. An attack with 50% piercing against a target mitigating 60% will still be mitigated by 30%.

## What is NOT in the math

Aincrad Legacy removed two classic hidden modifiers:

* **No size penalty.** Every weapon deals 100% damage to every monster size.
* **No mobbing penalty.** Being surrounded by many enemies does not weaken your defense.

What *does* still shape the outcome is your [armor type matchup](/aincrad-legacy-docs/combat-system/armor-and-attack-types.md) - the right armor against the right attack type multiplies with everything above.


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