Sly 1:Difficulty

Difficulty, also called suck, uSuck or noob mode, is the mechanic by which the game dynamically becomes easier or harder depending on your gameplay.

Sly 1
In Sly 1, the player is assigned a uSuck score between 0.0f and 0.1f for each individual level. These values are stored on the level states and persist between loads.

Sly 1 has three difficulty levels: easy, medium, and hard, each with a corresponding  struct in memory. On the easy and medium difficulty, uSuck increases by a set amount each time you die. On the hard difficulty, uSuck is locked at 0.

During a level transition, the game first calls. This function sets the difficulty level based on certain conditions such as what world the level is in, if the level is a hub or intro level, or if the key has been collected on the level. uSuck is not a factor in which difficulty level is set.

Later on, the game calls. This function compares the player’s current uSuck to the current difficulty level.
 * If the current uSuck is above the difficulty’s, it grants the player a silver charm.
 * If the current uSuck is above the difficulty’s, it grants the player a gold charm.

During normal gameplay, the uSuck is used to make certain aspects of the game more forgiving. For instance, on easy difficulty with a high uSuck you will be more likely to get more coins from breaking objects and killing guards.

Sly 2
In Sly 2, uSuck seems to be set on a per-mission basis. It ranges from 0.0f to 1.0f and increases each time you die or otherwise fail a job.

The uSuck value is used by the level scripts to make certain aspects of the game easier. For instance, in Moonlight Rendezvous, Neyla will normally only wait 5 seconds for you to catch up before you fail the job. As your suck increases, the time she waits also increases up to a maximum of 20 seconds.