How to build a failstack in Black Desert Online
September 26, 2026 · Updated September 30, 2026
A failstack is a counter that rises every time an enhancement attempt fails. The official Adventurer's Guide puts it plainly: "if you fail an enhancement attempt, the enhancement chance increases by 1". A success spends the whole stack and puts you back at zero.
The loop the system creates
Because failure is the only thing that builds a stack, and success destroys it, the system rewards failing on purpose in the cheapest possible place.
So the practice is to fail deliberately on something you do not care about until the counter is high, then spend that counter on the attempt you do care about. The stack belongs to your character and not to any item, so it carries from the throwaway attempts to the real one.
What failure costs, by item type
The cost of building a stack depends entirely on what you fail with.
| Item type | What a failure does |
|---|---|
| Weapons and armour | Maximum durability drops, and from DUO and +16 upward the enhancement level itself can fall. The guide notes "the higher the level of enhancement you are attempting, the greater the maximum durability decrease will be" |
| Accessories | The item is destroyed. The guide warns that "both the item you wanted to enhance and the ingredient item used for enhancement can disappear" |
That table is the whole reason stack building is done on cheap weapons and armour and never on accessories. Durability is repairable; a destroyed accessory is gone.
Memory fragments are the repair item for maximum durability on enhanced gear, which makes them a running cost of the activity instead of an occasional purchase.
The materials
Black stones do the enhancing from +1 to +15, in separate weapon and armour forms. Past that level the system moves to the PRI, DUO, TRI, TET, PEN sequence, which consumes different materials depending on the gear.
The Cron stone trade
Cron stones prevent the downgrade on weapons and armour and the destruction of accessories. They are consumed either way, on a success or on a failure.
The part that catches people out is what they do to the counter. The official guide is explicit: "if you enhance with cron stones, the equipment enhancement chance will not increase in case of failure."
So a Cron-protected failure costs you the stones and gives you nothing back. You cannot protect an item and build a stack in the same attempt, and that is the decision the system is asking you to make.
| You want | Use | Because |
|---|---|---|
| To build a stack | No Cron stones | Failure has to increase the counter, and Cron stops it |
| To protect a high-level item | Cron stones | The downgrade costs more than the stones do |
| To enhance an accessory you cannot replace | Cron stones | Failure without them destroys it outright |
Where the published information stops
The developer does not publish the probability table. The guide says only that "as the count increases, the success chance for the next enhancement gets higher", with no figures attached.
Everything circulating as a stack-to-percentage chart is community estimation from recorded attempts. Those tables are useful and they are not official, so treat them as estimates and check the in-game tooltip, which shows the current chance for the attempt in front of you.
The rates also change. Enhancement has been adjusted repeatedly since launch, and any guide carrying hard numbers is describing the patch it was written in.
Sources
Adventurer's Guide: Enhancement, Black Desert NA/EU, the official description of failstacks, failure outcomes and Cron stone behaviour
The in-game enhancement window, which shows the current chance for your item at your stack
How to decide when to use Cron stones, for the cost side of that trade