**RockerdedBR posted an interesting post last night on Reddit. It goes into detail about the Sanctuary of Iben Fahd, and in particular about the quantity of stones that can be obtained by opening the various chests.**

He assumes that the sanctuary somehow deceives us in two ways. The first is that the last chest of the 4th room is a decoy whose reward is distorted. The second is that collecting 377 Aspirant Keys to open all of the chests is exactly the same as using those keys to open the chests in the first room every day for a few days.

I put you below the statement of the number of keys and stones that each chest of the sanctuary conceals. Then, I translated the author’s words into French, which allows you to understand everything well;)

I removed chest #1 from the equation because it’s a free chest and I guess we all open it every day, even if you collect all 377 keys to open all the rooms at once. Because it’s free. 😛

So, you can see right away that Room 1 has a higher Stones/Key average than the other rooms.

Notice how from room 2 they increase the need for keys by 2 in each new chest and the rewards by 9. 9/2 = 4.5 and that’s how they keep the average at 4.5 in all rooms. Each new chest costs 2 more keys and gives 9 additional stones.

**1st delusion** : This changes in room 4 when we go from chest 19 to chest 20. Chest 20 requires 4 more keys instead of 2. But it gives the same number of rewards as chest 19 when it should have given 18 stones to maintain the average of 4.5 stones/key.

The fact is that these 18 stones were removed from chest 20 and placed in the FINAL chest in the center of the room and that is why this chest is free to be opened. To maintain the average at 4.5.

By removing these 18 stones and putting them in a chest in the center of the room, they create a mystery. What’s in the last chest? People would spend platinum just to get there and find out! And will be disappointed because this chest is nothing special. It’s just bait.

**So let’s move on to illusion #2** : We need 377 keys to open all chests in all rooms. And we get a total of 1704 stones by doing this.

Now, what if we used those 377 keys to only open the chests in Room 1? How many times could we open ALL the chests in room 1? And the answer is 25.13. Let’s round it up to 25.

Since coin 1 gives 75 stones (remember we’re not counting chest 1), we multiply that by 25.

25 x 75 = 1875.

HA! So coin #1 gives more rewards than all coins combined!

Not exactly. We forgot to add to the equation that there is a 5% chance that all chests in rooms 2, 3, and 4 can give triple rewards. So now the calculation is:

75 + 1629 x 0.95 + 1629 x 3 x 0.05 = 1866.90

So opening the 1st room 25 times gives 1875 stones. Opening all the coins at the same time gives 1866.9. It’s pretty much the same thing. It is not necessary to save 377 keys just to delay the improvement of stats as well as the chance to obtain Iben Fahd’s Tenacity.