Open Sonic v0.1.3 is released. Open Sonic is a free open-source game based on the "Sonic the Hedgehog" universe. It introduces a different style of gameplay called cooperative play, in which it's possible to control 3 characters simultaneously. Unlike most similar games, Open Sonic provides a greater level of interaction between the player and the levels. It's more than just a jump'n'run; the user must come up with some strategy in order to get through the levels.

Main features:
* It's portable! No installation required!
* Sonic-style physics (360° movement engine)
* Available in 7 languages: English, Portuguese, Spanish, French, Polish, German, Czech
* 2 levels + innovative items + extras
* You can create your own levels using the level editor
* Good performance even on old computers*

Open Sonic v0.1.3 Changelog:
* Tails has gained a new move: now he is able to pick up the other characters and carry them around
* Improved the level editor (it includes a bigger work area and new buttons)
* New level editor feature: grids
* New level editor feature: groups. You can now easily place groups of objects in your level. Useful to make loops and other common structures
* New level editor features: undo and redo
* New translations: German, Polish, Czech
* New songs: options screen and stage cleared
* New screen: options screen
* Removed the launcher program
* Improved the joystick programming. Just plug your joypad before starting the game and start playing!
* New icon
* New engine feature: bricks have a z-index property. Now it´s possible to design background/foreground bricks
* New engine feature: clouds. Clouds are types of bricks also known as "one-way platforms"
* Implemented jump sensitivity and spindash through multiple boxes
* Centered Tails´ sprites when jumping
* Improved the GUI/HUD
* New level: Chilpoctli Temple Zone (user-made graphics - thanks, Celdecea!)
* New level: Template (user-made graphics)
* Custom quests may be launched via command line using the --quest option (see opensonic --help)
* Removed the Master Quest
* New quests: Extra levels, Super Bosses
* Updated the docs
* Code improvements
* Bugfixes and lots of small changes

Download: Open Sonic v0.1.3
Source:Here