You have a 1/400 chance of unboxing a knife. You have a 1/66 chance of getting a case hardened karambit from that. You then have a 1/10 of that being st, a 1/14 chance of getting fn, and a 1/1000 chance of getting that pattern. Together this mean you have a 1/3,696,000,000 chance of getting this knife from a case. You would pay on average 10billion to get this from a case.
Edit: couldve sworn it was st but I guess not. Divide that by 10, so you’d end up with around 1billion spent on only revolver cases to get this knife