A Failstack is an indicator of the times you have continuously failed at enhancement. The more times you fail enhancement in a row, the more failstacks you obtain. The more failstacks you have, the greater your chances to succeed at the current upgrade.

Additional Enhancement Chance +
Valks Enhancement Chance +
Permanent Enhancement Chance (Hidden)


The total Failstack is the “Current Enhancement Chance” number in the Enhancement window.


Failstack Building Tip:

  • If available, check the “Durability” option, which increases chances of gaining a failstack. Durability option often doubles the difficulty of enhancement. This is only available for green grade gear at certain levels.
current enhancement chance

Failstack Terms Defined

  • Percentage: the percent shown in the diamond icon at the top. It’s the chance the current Enhancement will succeed.
  • Additional Enhancement Chance: This character’s failstack. An indication of the times this character has failed enhancement in a row. (Enhancement Chance is reset upon enhancement success.)
  • Valks’ Enhancement Chance: increase this up to 10 from Valks’ Cry and Fairy’s Blessing (or max 13 with Herald’s Journal)
  • Current Enhancement Chance: total Failstacks
  • Hidden Permanent Enhancement Chance: up to +4 family-wide failstack from completing Rulupee Adventure Log.
  • Enhance: Check this option if your main goal is to increase enhancement level of the gear piece and NOT to gain a Failstack.
  • Durability: Check this option if you are trying to increase your Failstack number for a later enhancement to upgrade a different gear piece. (Not available for many higher tier gears.)
  • Force-Enhance: 100% Enhancement Chance at a fixed Black Stone cost and also requiring a large amount of Max Durability. (Not available for many higher tier gears.)
  • Caphras: 100% Enhancement Chance using Caphras Stones.
  • Extract Chance: use a Blacksmith’s Secret Book to store the current Failstack for later. (Details below)
  • Exchange Chance: store your current Failstack in Naderr’s Band to use later. (Details below)

Failstack Building the Easy Way

Building a Failstack of 30 can be very easy using 84 Black Stones.

This method of failstacking does not rely on luck. The bad part is it may be more expensive and less exciting for players who enjoy gambling. But this is the safest method of enhancement.

Failstacks Step by Step:

  • Right Click a Black Stone
  • Click the + sign next to “Additional Enhancement Chance”
Black Stones Failstack
84 30
53 25
33 20
21 15
12 10
5 5
Failstack Black Stones

Failstack Building via RNG

Ready to gamble to win big, maybe? Purchase cheap Reblath Shoes sold by Tranan Underfoe in Velia. Then gather up some Black Stone. Right click the stone and click to enhance. Keep failing on enhancement until you have a failstack of 22.

If you have more Black Stone, you can use Militia weapons instead. Purchase from Alfredo in Velia.

The goal is to get your failstack item to +14. The greatest chance for obtaining a cheap failstack occurs as you try to upgrade +14 to +15. There is only a 2% chance that the armor/weapon will enhance with 0 failstacks.

Because cheap gear is used, building failstacks isn’t as expensive. (Reblath shoes only cost about 13k silver. Compare that to the cost of repairing boss gear with Memory Fragments.)

Tranan Underfoe

BDO Blacksmith Shop: Reblath


You can also build a new failstack or add to your existing failstack by destroying already enhanced gear.

To view details, please view our Devour Guide.


Failstack Costs

BDO Enhancement: Recover Max Durability

Failstacks are a good thing, but they do cost you! Every time you fail enhancement, you lose at least 5 Max Durability on the item you are trying to upgrade, plus your enhancement mats.

For higher level gear enhancement of DUO+, you can actually downgrade the item. So a DUO could become a PRI on failure. (Cron Stones prevent the building of failstacks.)

Accessories are not recommended to build failstacks, due to the higher cost. Both accessories are destroyed upon failure.

Max Durability is repaired by visiting the Blacksmith and clicking Repair > Recover Max Dur.

Max Durability can be repaired by destroying another of the same kind.


Max Durability lost often depends upon the Enhancement consumable used.

Black Stones: -5 Max Durability.
Concentrated Black Stones: -10 Max Durability

Total Cost of Failstack = Black Stones + identical gear for repair or Memory Fragments.


Cleanse Gear to Drop a Level

If the item you are building your failstack on accidentaly upgrades to +15, then you can go to a <Blacksmith> to downgrade it to +14. Click the option called “Cleanse Gear” for 100k silver.

Increasing to +15 means you lost your entire failstack. You will have to start over building a new failstack.

For this reason, some players refuse to use gear that is not already useful and demanded on the Marketplace. If it does happen to level up, then they forgo cleansing and have something they can sell. (Example: popular green gear like Heve helmets.)

Example Failstack Building Strategy:

  1. Failstack 1 to 22: click +14 Reblath Shoes
  2. Failstack 23 to 28: click PRI Heve Helmet
  3. Failstack 29 to 43: click DUO Heve Helmet
  4. Failstack 44 to 88: click TRI Heve Helmet
  5. Failstack 89+: click TET Heve Helmet

In the above failstacking example, you can keep or sell the Heve Helmets that accidentally upgrade.



BDO Cleanse Gear

Failstack Building Tips

  • Failstack Saving:
    • open up all 16 Naderr’s Belt slots, enabling you to save up to 16 failstacks to use on all characters
    • each character can build a seperate failstack, to save for later
    • switch characters, if your failstack is too high for the current enhancement
    • buy Blacksmith’s Secret Books to save failstacks


When doing enhancement, there will come a point when the failstack gets too high and you need to save it for later.

There are several options for this.

The most difficult one is to switch characters. It’s more time consuming. You have to transfer all your enhancement mats via storage and wait for the game to load.

Naderr’s Band is a huge improvement. I highly recommend, if you plan on doing much enhancement. And it doesn’t cost silver, unlike Blacksmith’s Secret Book.

Valks’ Cry

Pearl Costume Valks’ Cry Extracted Cron Stone Extracted
Helmet 15 45
Armor 34 102
Gloves 13 39
Shoes 13 39
Main Weapon 23 69
Sub-weapon 14 42
Awakening Weapon 28 84
Total 330 420
473 million Silver


Valks’ Cry adds +1 to the Failstack, increasing the Valk’s Enhancement Chance.

Valks’ Cry increases the Failstack by a maximum of 10. (Get +3 Max Valk’s Enhancement Chance from Herald’s Journal).

Valks’ Cry from Loyalties:
Purchase Valks’ Cry with 200 Loyalties. It’s limited to 5 per Family per week.

Valks’ Cry from Pearl Costumes:
Pearl costumes can be turned into Cron Stones or Valk’s Cry at a Blacksmith.

valks cry

Note that you can also purchase Advice of Valks via Loyalties.

Advice of Valks gives you an instant failstack, as long as you don’t currently have a failstack. Passive enhancement chance from Rulupee’s Adventure Log doesn’t prevent you from using these items.

Loyalty Item Loyalties Purchase Restrictions
Advice of Valks (+50) 2500 Limit 1/month: resets on the 1st every month
Advice of Valks (+60) 5000 Limit 1/month: resets on the 1st every month
Advice of Valks (+70) 7500 Limit 1/month: resets on the 1st every month
Advice of Valks (+80) 10000 Limit 1/month: resets on the 1st every month
Valks’ Cry 200 Limit 5/week: Resets on Monday




advice of valks 40

Fairy’s Blessing

Fairy’s Blessing is just like using Valk’s Cry. It will add +1 to Valks Enhancement Chance. Any combination of Valk’s Cry and Fairy’s Blessing cannot exceed +10 (Get a permanet +4 from Herald’s Journal).

  • Laila’s Petal can be exchanged for Fairy’s Blessing with Fairy Queen Theiah or Ceilyn. (Laila’s Petal can be obtained by defeating monsters, Gathering, and Fishing.)
    • Laila’s Petal x10 → Fairy’s Blessing x1
  • You have to complete the quest “[Awakening] Traces of Edana” or reach Lv. 30 to use this item.
  • Ceilyn is located to the right of Herawen in Kamasylve Temple. However, this exchange will not be activated when the quests ‘Laila’s Scattered Petals’ and ‘Mysterious Companion’ are under progress.
fairy's blessing

Failstack of 20 to 50 with Dragon Scale Fossils

You can turn in an item that drops from mobs in Dreighan to get an Advice of Valks.

Dragon Scale Fossil Locations:

  • Tshira Ruins
  • Blood Wolf Settlement
  • Sherekhan Necropolis (Day, Night)
  • random Garmoth attack event that drops “Old Drieghanese Crate” [gives x5 – x10]

Dragon Scale Fossil Exchange Rates:

Required Item

Enhancement Item
Dragon Scale Fossil x20 Advice of Valks (+20) x1
Dragon Scale Fossil x50 Advice of Valks (+30) x1
Dragon Scale Fossil x150  Advice of Valks (+40) x1
Dragon Scale Fossil x400  Advice of Valks (+50) x1


dragon scale fossil

Sherekhan Necropolis has a recommendation of 200 AP and level 60. map

BDO Sherekhan Map


Blood Wolf Settlement has an AP recommendation of 170+ and level 58+. map

BDO Blood Wolf Settlement Map


Tshira Ruins has a recommended AP of 150+ and level 57+. map

BDO Tshira Ruins Location Map

Dragon Scale Fossil Exchange NPCs

Dragon Fossils can be exchanged to a <Skill Instructor> in many major cities.

City Dragon Fossil NPC
Velia Tachros
Heidel Cruhorn Wyrmsbane
Calpheon Valks
Altinova Abdul Jaum
Valencia City Rabam
Sand Grain Bazaar Amir
Grána Hazel Azealia
Duvencrune Akasak
O’draxxia Samala Elsha
Eilton Ulan

Blacksmith’s Secret Book

Blacksmith’s Secret Book is used to store your current Enhancement Chance. This will make your current Failstack fall to 0, but enables you to start again and use your stored Failstack for a more suitable item.

Blacksmith’s Secret Book is available at any <Blacksmith> in town.

  • Blacksmith’s Secret Book – 20: 100k Silver
  • Blacksmith’s Secret Book – 30: 400k Silver
  • Blacksmith’s Secret Book – 40: 1 million Silver
  • Blacksmith’s Secret Book – 50: 2 million Silver
  • Blacksmith’s Secret Book – 80: 10 million Silver
  • Blacksmith’s Secret Book – 100: 20 million Silver
  • Blacksmith’s Secret Book – 500: Pearl Shop only: 200 Pearls for 1, 2000 Pearls for 11

Blacksmith’s Secret Book converts your Enhancement Chance amount into an Advice of Valk’s with equal Valk’s Enhancement Chance.

The number shows the maximum amount of Enhancement Chance that you can store. For example, if you currently have an Enhancement Chance of +41, you cannot use Blacksmith’s Secret Book – 40. You must buy Blacksmith’s Secret Book – 50.

blacksmith secret book shop
blacksmith's secret book 500

Blacksmith’s Secret Book – 500 stores up to a 500 failstack is only available via the Pearl Shop.

Blacksmith’s Secret Book are not normally available via the Loyalty shop. Sometimes there are sales and coupons in the Pearl Shop.


Failstacks using Naderr’s Band

Naderr’s Band lets you save up to 16 failstacks for later, without having to switch characters or buy a Blacksmith’s Secret Book. Once they are unlocked, you can freely load and unload failstacks. These Nadder failstacks are accessable to every character.

Naderr’s Parchment unlocks up to 16 slots in Naderr’s Band.

Naderr's Band

Unlock All 16 Naderr’s Band Slots:

  • Black Spirit Quest: [Naderr’s Band] Magic of the Dark Energy
    • level 58+
    • talk to Black Spirit, click Suggested tab
    • quest line is short and simple, just talking to several NPCs
  • spend 20,000 Loyalties (limit 1)
  • Pearls: 1,100 each (buy 14)
BDO Naderr's Band: Pearl Shop Cost

Naderr’s Band Cooldown:

  • When exchanging an enhancement chance increase value of +300 or higher, a cooldown of 5 sec will be applied.
  • Valk’s Enhancement Chance does not count toward the cooldown.

How Many Failstacks Should I Use?

Failstacks have an optimal range. For many enhancement levels, there are “Softcaps”, in which you get significantly less Enhancement Chance from increasing to the next Failstack.

For example, 70% Enhancement Chance is the Softcap for the majority of armor and weapons. Going over this, will make enhancing that item extremely more expensive.

Keeping Softcaps in mind, there is an optimal range that most players use for certain levels of enhancement. For this reason, players say to stop failstacking or to save that Failstack, after you have gained a certain number. This is in order to use that too high failstack on an item of a lower enhancement level. Using a very high failstack on a low level weapon would be a waste of the silver you spent gaining that high failstack. (Example: don’t use a 100 failstack on upgrading a +15 to PRI.)

Some levels of enhancement, like TET, PEN, and +15 have no soft cap and these are difficult most of the time. (There are now beginner gear options that have unusually high levels of enhancement. Naru Gear and the next step up, Tuvala Gear.)

Another Adventurer’s Choice

You can check the enhancement chances used by other players in the Another Adventurer’s Choice window when you have a gear in the enhancement window.

  • Click the button next to Current Enhancement Chance when enhancing through the Black Spirit (,).
  • Info from Another Adventurer’s Choice will refresh when the window is opened.
  • Gear without enough data on enhancement chances will be displayed once there is enough data to be assessed.

For more info, please view our Failstack Charts that show softcaps.

You can also use our Failstack Calculator. The calculator will try to determine how useful a Failstack is for a certain level of enhancement.