How to Unlock The Wrestler
You unlock the Wrestler by beating the Slums using only your fists. This means you can’t use melee or ranged weapons. You can equip them, but if you use them, you won’t unlock the achievement.
The easiest way to unlock Wrestler is to use Gangster Crepe/Blahd (doesn’t matter which one) and use your gang members to complete your missions. Gang members are found pretty mucheverywhere throughout Slums and Industrial, but more so in Slums.
A good tip is to turn off “Auto Equip Weapons” in the options. It stops your from automatically equipping a weapon when you pick it up.