In Pink Matter, you have to use droids to close up all of the portals in each level. You do this by commanding the droids to push a block (called pink matter in this game) into a portal to close it. Your droid loses an appendage each time a block is pushed, and when a portal is closed it automatically turns into a solid wall.
Should a droid loses all of its appendages, it will cease to exist, hence careful planning is required because it’s easy to make a wrong move and end up with not enough droids for solving a puzzle. The game features roughly ten levels to play through, and as usual you can undo moves or reset a puzzle by using the Z and R key.
Pink Matter is available to play here.