You play as Vent and have to make your way through 8 worlds with 10 levels in each world to help the inhabitants to get rid of all the monsters that are roaming the place. During the game you can buy new abilities to wall-jump, levitate, double-jump, etc., this will be needed to complete all the challanges that this game throws at you! There is also plenty of room to simply explore all the worlds and their levels and many secrets to be found (even I have lost track of all the secrets and are surprised sometimes). It is at the prototype stage but is fully playable, in the prototype version there are 4 worlds with 10 levels each + town in each world.
Download here: http://dl.dropbox.com/u/8443610/venture_newproto.zip