In total you could get

x45 Black Spirit Doll Lv 0

I.

1. open all x45 Black Spirit Dolls Lv 0

2. mark the Challenge Chest Lv 1 

2. select maximum quantity (45)

3. use the "Comfirm" button

II.

4. open all Black Spirit Dolls Lv 1

5. mark the Challenge Chest Lv 2 

6. select maximum quantity

7. use the "Comfirm" button

III.

8. open all Black Spirit Dolls Lv 2

9. mark the Challenge Chest Lv 3 

10. select maximum quantity

11. use the "Comfirm" button

IV.

12. open all Black Spirit Dolls Lv 3

13. mark the Challenge Chest Lv 4 

14. select maximum quantity

15. use the "Comfirm" button

V.

16. open all x4 Black Spirit Dolls Lv 4

VI.

17. my final profit

sure choice:
Chaos Crystal x50
50 x 45 = 2,250 Chaos Crystals

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lucky pick:
Lvl 1, Lv 2, Lv 3, Lv MAX Challenge Chest: different results
my result = 3,955 Chaos Crystals