BioWare's Sonic Chronicles: The Dark Brotherhood, its hedgehog-related DS RPG, will provide a pretty healthy amount of play-time, if this Gamespot interview's to be believed.
"For the full single-player gameplay experience, you can expect about 20–25 hours," said art director Joel MacMillan.
Yep, that means there's multiplayer.
"There will be some multiplayer ‘trading’ to take advantage of," MacMillan added.
Game's out this year. Thanks, MaxConsole.