Twelve characters, four numbers, eight lowercase a-z

[chrisjriddle]

Thanks for tips! What if I wanted to make a limit that only 4 out of 12 characters could be numbers, and the rest had to be lowercase letters, albeit in no particular order, is there a rule to handle this type of specificity? Because If I can't narrow it down somehow, then according to hashcat, it looks like:

"Time.Estimated...: Next Big Bang.."

lol