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Some fans didn't take to Trine 3 because of its length and attempt at 3D gameplay, but developer Frozenbyte says that Trine 4: The Nightmare Prince returns the series to the 2.5D gameplay that made it famous.
The game also reunites fans with the franchise's three heroes, tasking them with defeating the evil unleashed by Prince Selius' waking nightmares, via a new combat system as well as physics-based environmental puzzles. The Nightmare Prince also includes four-player co-op (local and online), new skills, and more.
In other Trine news, Frozenbyte has announced Trine: Ultimate Collection, featuring all the games in the series and extras such as a physical map of the world, a code for a digital artbook, a reversible cover sheet, and a soundtrack download code.