Item Defilement is a mechanic exclusive to The Abyss. This mechanic is crucial in late game to ensure that players will have proper gears without the hassle of grinding for loot and soul-matching manually. In short, by defiling an item and then successfully leaving the Abyss with that defiled item, the player has a chance to:
Improve the item quality to the next tier
Common to Uncommon
Uncommon to Rare
Rare to Exotic
Exotic to Divine
Divine to Ethereal (Note: Items defiled on floors below 21 has no chance to become Ethereal)
Increase the item level and +value (only applicable to Divine and Ethereal items and from floor 21 onward)
Items defiled on floor 21-30 will have +value ranging from +20 to about +28 (equivalent to Way of the Wise difficulty)
Items defiled on floor 31-40 will have +value ranging from +31 to about +38 (equivalent to Way of the Nioh difficulty)
Items defiled on floor 41 onward will have higher +value, follows the formula:
+Value = (Floor# * 0.1) + 35 (+/- 3)
For example, by leaving the Abyss on floor 160, defiled items will have +value ranging from +48 to +54. However, it is very rare to have +54 in actuality. In fact, most of the items will have +value ranging from +48 to +51. Higher +value does appear, but rarely.
Acquire a Grace for non-set items, if they become Ethereal after defilement
This is only applicable for items not belong to a set.
This is only applicable for Divine items turning into Ethereal after defilement.
Items which already have a Grace will NOT acquire a new Grace after defilement.
There are 2 ways to acquire defiled items in the Abyss, self-defiled or looted from strong enemy/bosses.
A quick note about defiled items looted from enemies/bosses: All rules mentioned above applies to defiled loot, i.e. defiled items picked up under floor 21 have no chance to become Ethereal. Also, the affixes of those defiled items are determined at the moment they dropped, so save-scumming has no effect on them. The things that are determined at the moment players leave the Abyss is the Grace, and +Value.
In order to defile an item yourself, you need:
The item itself, of course. Preferably Divine item at Level 300. (Aside from weapons and armors, accessories can be defiled too).
A substantial amount of Amrita. In order to defile a Level 300 Divine Melee weapon, about 550 millions Amrita is needed. On the other hand, a Divine Armor at Level 300 will need about 340 millions Amrita. The amount of Amrita required depends on the quality of the item, its level, and the number of defilement it has been through. Similar to soulmatching, the cost will increase drastically after a few defiles.
A Droplet of Decay. This item is exclusive to the Abyss. It is rare drop from normal enemies in Abyss, and usually Abyss Bosses will drop 1 or 2.
Item should only be defiled from floor 21 onward. However, the chance of the item become Ethereal is not high on floors 20s. To have a better chance, it is recommended to do so or floor 31 or higher.
By praying at any Shrine in the Abyss, a new function called Defile will appear:
After defiling, the item will turn gray, all affixes disappear, and all values become ???:
Note that right after defiling, the DEFILED ITEMS will be 0. This value indicates the chance of a successful defilement. It will increase by 1 every time a floor is completed, but it is capped at 3. In other words, by completing 4 floors after defiling, the chance for it to become Ethereal is maximized, and it is safe to leave the Abyss.
Some important things to note about defiling:
If a Divine defiled item does not belong to a set, and it has one empty slot, a Grace will fill that slot, as shown in the example below:
If a Divine defiled item does not belong to a set, and it has all 7 slots filled, a Grace will replace a random slot (even inheritance slot). The example below show that the Grace has replaced Skill Ki Damage affix:
*For Divine items that belong to a set, it will not acquire a Grace, but it still have a chance to become Ethereal:
By leaving on specific floors, the Graces applied on defiled Ethereal items will belong to one of the set according to the formula below:
Set 1: Floor# / 3 = X.000
Set 2: Floor# / 3 = X.333
Set 3: Floor# / 3 = X.666
For example, if you want to get Izanagi's Grace, you should leave on floor 25, 28, 31, and so on.
As mentioned above, to maximize the chance to get Ethereal from defiled items, 4 floors need to be completed. So, again, to get Izanagi's Grace, one should enter the Abyss on floor 22, defile the item, then complete floor 22, 23, 24, then leave after defeat the boss on floor 25.
Note 1:Ethereal items picked up in the Abyss also follow this rule.