catacombes equiptment challenge question

[WishBlade]

So i`ve asked this question before but dident really get an answered, So:

What is the equipment challenge thing when you enter the catacombs?
I can see that he "Daily free attempts" are the times i can enter without a key and this quickly changes to 0/1 after my catacombs run. However the equipment challenge always says 1/1 beside it and I fell like i`m losing out on something, will the equipment challenge change to 0/1 when i do something? and what is this something?

[†Castielâ€]

Equipment Challenge = Crypt Key
When you ran out of Crypt Key, you can only enter once a day.
or you can buy Crypt Key in Shop for 75 Balens Each