From the moment you create your character in Mafia Returns, you have a set of "Skills". These skills are generated with the "Roll" feature in the character creation page. From that moment, you set out to improve (most of) these skills as you play. These skills are the basis for your interaction with the game, so choose them wisely.
Referred to as "Marksmanship" in the character creation page, this skill is used to attack and end the lives of other players. This skill is used in the Wack and BG Wack features. When you start, it is wise to visit the Shooting Range until you can train no more. Once you've use the Shooting Range as much as possible, you can continue to improve your Wack skill by shooting other players and Non-Playing Characters (NPCs). This is a very dangerous skill to train, so it is wise to contact your leader before you make the step from Shooting Ranges to training on NPCs and other players. The development of this skill allows your character to kill others, so it can be a very valuable asset if trained well. As this skill improves, you will be able to kill higher-ranked and better-protected players.
Referred to as "Physique" in the character creation page, this skill is used to attack players by stealing their money. This skill is used in the Pickpocket (PP) feature, and the only way to increase your PP skill is to pick people's pockets. The maximum amount of money you can steal from a player is $5,000. However, if a pickpocket is performed in retaliation (someone pickpockets you first), you have the ability to "Mug" them. This is significantly more harmful to your target, as you can steal significantly more than $5,000 and jumble their flight and wack timers. Typically, players who invite pickpocketing have "Pickpocket friendly" in their profile, and will not attack you if you pickpocket them (though they do normally request that you send the money back). However, it is wise to always check the rules for the city you are in to ensure that no harm will come to you for pickpocketing someone. If you aren't sure, just stick to people you know.
Referred to as "Stealthiness" in the character creation page, this skill is used when attacking players. This skill cannot be increased from when you sign up, the higher it is, the more likely your name will be shrouded in the "Witness Statement" for your attack. This skill is supplemented by Vision. The higher your stealthiness, the more vision necessary to see your name in the locals and to decipher your name in witness statements.
Referred to as "Defense" in the character creation page, this skill protects you from attacks. This skill cannot be trained, but can be increased by purchasing Bodyguards.
Note that having 100 Defense skill will give you the benefit of a 5% additional failure rate when wacked at. 99 Defense will give you the benefit of a 4% additional failure rate when wacked at. 98 Defense will give you the benefit of a 3% additional failure rate when wacked at. 97 Defense will give you the benefit of a 2% additional failure rate when wacked at. 96 Defense will give you the benefit of a 1% additional failure rate when wacked at.
Referred to as "Breaking and Entering" in the character creation page, this skill provides you with the ability to break other players out of Jail. This skill is trained by the successful breaking-out of a fellow player (it is wise to start with players being guarded by very few guards). This skill is quite valuable, as jail-breaking provides experience that goes towards increasing your rank (Gangster, Goomba, Earner, etc.). This skill does not decay, so once you are able to break out 20-guard players (admins), you will be able to consistently break them out (though there is a small element of chance to this, so you may fail a jail-break at any time, regardless of guard number or skill).
Referred to as "Intimidation" in the character creation page, this skill determines your success in crimes (Petty Crime and Felonies). This skill is trained (rather quickly) through successfully completing crimes. Once you're able to successfully "Rob the Local Post Office" consistently, training this skill loses its importance.
Referred to as "Street Smarts" in the character creation page, this skill determines how well you can identify your fellow players in Locals and Witness Statements. This skill is trained by posting in the Streets and Business District forums. As this skill increases, you will be able to see players with higher stealth, and witness statements will contain less asterisks (*), allowing you to decipher the culprit.