Picking a Lock with Don and Nesto's Help Edit
Don and Nesto, with their "education in fine mechanics", have no difficulty picking a lock. They first demonstrate this skill in the Forest Hut when they open the locked basement door of their uncle Tarka's house and later when they unlock the gateway to the Southern Bay.
Later in the game, at the third Gateway Idol, Scarlett learns the Eye of the Lost mental skill, which allows her to see the dead. After she masters this skill, Don and Nesto, who meanwhile have been killed by Assassins, help her crack most of the locks she encounters.
Locks can block either doors or chests. When Scarlett tries to "use" a locked door or chest, she automatically drops into the Twilight World, where she can see Don and Nesto. They then show Scarlett, through gestures, in what sequence to toggle the four picks. The sequence can be anywhere between four and eight colors long (e.g., red-red-green-blue). Most doors use only a four-color combination. Chests appear to have a longer color combination if they contain more valuable contents; also, locks in the Inner City and the Arsenal District tend to have longer combination. Once a lock is picked, it disappears.
The lock-picking passage into the Twilight World costs no mental energy, and the passage takes as long as she needs to toggle the picks.
Some locks must be picked as part of a Quest. For example, after Scarlett encounters the third Gateway Idol, the temple door is thrown shut by a panicked Nox, and Scarlett can count herself lucky that she just learned the Eye of the Lost so she can reopen the door.
Lock picking increases Scarlett's experience: Picking a four-color lock (either a door or a chest) adds 15 experience points, picking a 6-color lock, 30 points, and picking an 8-color lock adds 50 experience points.
Although lock picking is no mental or physical skill in the strict sense, it can be seen as a skill in the wider sense, hence the category.