Ars Demonium Invocatum

Ars Demonium Invocatum is a puzzle game in which you decipher a book of demonology and learn to control demons. Each level describes a demon and asks you to find signs that combine to form a target symbol, using the fewest moves possible. The symbols combine according to the XOR principle, and the signs you find form the key to controlling the demon. Symbols change with each attempt, so you must choose them again.

The book and its history

Demons have existed since the earliest chronicles, hiding in humanity’s shadows and influencing its history. Small communities have grown into huge cults, leading the Inquisition to burn entire cities. Demons generally pursue their own aims, but rituals and spells can summon them and compel them to obey; this binding magic grants power, though contact with demons eventually destroys the sorcerers who use it.

Legends tell of a master who learned the names and symbols of demons, allowing him to use them without harm. He recorded his research in a book called Ars Demonium Invocatum. Hunters who sought the book died, and both it and the sorcerer vanished from history. Now the book is in your hands, and you must decipher it to gain its knowledge.

Levels and chapters

The game has three chapters, each with 18 levels. Your character grows stronger with every level you complete. Finishing the chapters unlocks additional features that make the puzzles easier.