NP Purchase Stamp Usage Guide
When you purchase an NP product, you are taken directly to the Stamp page, and the stamp you earn is applied immediately.
Each time a stamp is applied, one item is randomly excluded from the reward list.
Once 4 stamps have accumulated, after the 4th stamp is applied you can randomly obtain one of the remaining (non-excluded) items.
Once you accumulate 4 stamps, you obtain 1 item from all items remaining in the list above.
1
What Is a Stamp?
When you purchase an NP product, 1 stamp corresponding to that product is activated.
Once the purchase is complete, you are taken to the Stamp page, where the activated stamp is applied automatically.
Each time a stamp is applied, one item is randomly excluded from the reward list.
You do not need to select or use stamps separately — they are applied automatically after you purchase an NP product.
Stamp Flow
2
Stamp Types
The type of stamp applied depends on the price of the NP product purchased.
Products That Apply a Stamp
Of the 6 price tiers in the NP shop, a stamp is only granted when purchasing the 4 products above.
The 800 NP·1205 NP products are not eligible for stamps.
Blue Stamp
Purple Stamp
3
What Happens When a Stamp Is Applied?
Each time 1 stamp is applied, one item is randomly excluded from the reward list.
When you obtain a Blue Stamp, 1 item is excluded from the Blue Stamp's reward list; when you obtain a Purple Stamp, 1 item is excluded from the Purple Stamp's reward list. Since these are separate lists, one stamp does not affect the other list.
In other words, this structure consists of three steps: Stamp Obtained → Reward List Exclusion → Final Reward Obtained.
Example
Let's assume you obtained 3 Blue Stamps and 1 Purple Stamp, for a total of 4 stamps.
The final reward is automatically determined by chance from among the remaining items in the combined Blue and Purple reward list.
Therefore, players do not choose which item to exclude themselves — the excluded item is determined by chance when the stamp is applied.
4
At What Odds Are Items Excluded?
Each item in the Blue and Purple reward lists has its own base exclusion probability.
When one reward is excluded, that item's probability is redistributed proportionally among the remaining items.
So no matter how many items are excluded, the probabilities of all items remaining in that list always add up to 100%.
Click the checkboxes to exclude items one at a time.
You can see how the probabilities of the remaining items change, and confirm that the total always stays at 100%.
| Exclude | Item | Status | Exclusion Probability |
|---|---|---|---|
| Loading... | |||
Click the checkboxes to exclude items one at a time.
You can see how the probabilities of the remaining items change, and confirm that the total always stays at 100%.
| Exclude | Item | Status | Exclusion Probability |
|---|---|---|---|
| Loading... | |||
The total exclusion probability for the Purple list and the total for the Blue list are each separately 100%. The two lists are never combined.
5
At What Odds Is the 4-Stamp Reward Obtained?
After the 4th stamp is applied, you can obtain 1 item at a set probability, based on the items remaining across the Purple and Blue lists.
Try It Yourself
Press a button or click a checkbox to exclude an item.
Each time an item is excluded, you can see how the probabilities of the remaining items change.
10 items remaining
| Exclude | Item | Status | This Exclusion's Probability | Final Reward Probability |
|---|---|---|---|---|
| Loading... | ||||
- in the simulation
※ In practice, the items eligible for exclusion may vary depending on the stamp application stage.
6
Stamp Progress at a Glance
7
Please Note
- When you purchase an NP product, the stamp corresponding to that product is automatically activated and applied.
- Players do not need to select or use stamps themselves.
- Each time a stamp is applied, one item is randomly excluded from the reward list.
- The items eligible for exclusion may vary depending on the stamp application stage.
- The exclusion probability is determined based on each item's weight.
- Once 4 stamps have accumulated, after the 4th stamp is applied you randomly obtain 1 of the remaining items.
- The final reward probability is also determined based on the probabilities of the remaining items.
- After obtaining the stamp reward, the reward list is reset, and the process can start again the next time you purchase an NP product.