Into The Lion's Mouth
Received from: Doctor Lavarius [New Ashos] (M23:9) or stranger (M23:11)
Once you're inside the "Lion" (M23:13), you will notice a guard by the door - George You won't get past him without having a membership card. You can try to bribe or fight him.
Whichever option you choose, Lexington will eventually appear. Tell him that you'd like to talk with him and then follow him to his office. The queue for the membership card is long, but you can speed things up by completing a task for the director. You have to teach a lesson to one of the competitors - a man known as Sammy the Bull. He lives in a house nearby the casino (M23:14).
You will unlock [Sammy the Bull].
Sammy the Bull
Received from: Lexington [New Ashos] (M23:13)
Once you arrive at Mangano's whereabouts (M23:14) you will notice that the door is locked. Hide behind the crates and wait for one of the guards to appear. Kill him silently, take the key and open the door. Inside you will see a dead man. Someone has made it here first and killed Sammy.
You will unlock [The Specialist].