Professor Layton and the Diabolical Box/Gameplay

Puzzles
Like other installments of the series, Professor Layton and the Diabolical Box is all about solving puzzles. You're required to solve certain puzzles to move the story onward. Puzzles can be found everywhere, from talking to people to checking objects. Any puzzles solved will be recorded in the Puzzle Index. Puzzles can sometimes be missed, such as forgetting to solve a puzzle in a location you won't return to, but you can always access Granny Riddleton's shack for unsolved puzzles.

All puzzles possess a set Picarat count, which is a rough measure of how difficult the puzzle is. Solving the puzzle awards Picarats, but quitting or getting a wrong answer will reduce the number of Picarats you get until a set level. Picarats are used to unlock bonus content which can be accessed from the main screen. Don't worry about not having sufficient Picarats to unlock everything. As long as you solve every puzzle, even if you reach the minimum amount of Picarats obtainable for each one, you'll have enough to view all the bonuses.

Hint Coins
Hint coins are another major part of gameplay. Hint coins are used to unlock hints, at one hint per hint coin. Each puzzle has three hints which serve to guide you to the solution if you're stuck, though all three will be unlocked free of charge once you solve the puzzle. You start off with ten coins and can collect more by checking certain spots. Like puzzles, hint coins are missable, but there is no way to get ones you lost. Don't use hint coins liberally, as there aren't enough coins for the whole game to unlock hints in every puzzle.