Abdec

Abdec is a pen and paper puzzle book about discovering the writing system of the Abb creatures. Through logical deduction, you’ll need to place Tetris-like shapes into a grid to satisfy the rules. However, the rules of Abdec are taught without words, requiring you to infer the rules based on whether they would give you unique solutions across multiple puzzles.

Each puzzle in Abdec is represented by an irregularly-shaped grid with some letters written above it. Each of these letters represents a shape that needs to be placed into the grid, which you’ll mark by drawing outlines or shading with your pencil. Throughout the book, additional mechanics will be introduced, such as little Abb creatures that appear in some of the cells and restrict the placement of shapes in some way.

Unlike in most rule-discovery games, the puzzles in Abdec cannot give you feedback (since it’s made of paper!). The rules must instead be inferred based on the given constraints and knowing that every puzzle has a unique solution. This can be quite unusual to wrap your head around, but if you can conjure up a consistent rule set that gives unique solutions across every puzzle, then you’ve probably figured out the correct rules. Sometimes, rules that you have discovered can be subtly incorrect, so you’ll have to reevaluate what you think you know and experiment with new ideas.

Throughout the book, curious players may notice unusual markings or cryptic notes scrawled throughout the book and wonder if they mean anything. Those with the most attention to detail will follow these clues and find plenty of hidden puzzles and secrets.

The game’s physical book form is a joy for hands-on players much like its predecessor LOK — there’s nothing more satisfying than flipping through a book as you solve puzzles. The book also comes with a plastic sheet, so that you can make notes with a whiteboard pen without making a mess of the pages themselves, but there is also a PDF version that you can alternatively print for yourself. Abdec was the recipient of Best Pen and Paper Puzzle award at the 2023 Thinky Awards.

This description was written by Hira and edited by Oriane Tury.