Professional Difficulty Level offers extended replayability, new game features, a separate mastery track with unique rewards, tweaked game mechanics and new AI behaviour that combine to create an entirely new experience for all players, whether they’re looking to test themselves in a more challenging environment or earn bragging rights at the top of the leaderboards, which are now separated between difficulty levels.
Professional Difficulty Level can be selected for all Story missions in Season One, excluding the Prologue. To unlock this new difficulty level, you will need to reach Mastery Level 20 for each location. As a clear example; reaching Mastery Level 20 on Paris will unlock Professional Difficulty Level on Paris. Our ‘live content’ such as Elusive Targets and Escalation Contracts will only be available on the default difficulty level, which we are now calling Normal Difficulty Level.
Full release notes for the January Update will be published before the update arrives on January 31st, the same date that HITMAN – The Complete First Season is available on disc.
Source: Hitman