One Good Game Studio's Parallel Levels is a challenging puzzle platformer with a twist. Namely, that you're always playing at least two levels at the same time... the last one you finished, and a new one with another character, and all blocky minions move simultaneously, so you have to time all your movements to get around the obstacles in both stages onscreen! Just use the [WASD] or [arrow] keys to move and jump and make for the door at the end of each level(s), making sure to grab any keys to unlock doors blocking your way, and nab stars to unlock more worlds. If any character touches a hazard, you'll have to restart!.
Initially, Parallel Levels is fairly easy thanks to the fact that you don't have to get all your characters to a level's exit at the same time. But as the stages increase in complexity and the number of block dudes you have to control goes up, the game quickly grows teeth. Different worlds bring different elements, like treadmill blocks that push you in different directions and collapsible bricks. So what's the problem? Touchy controls. Movement feels a little slidey, which makes the precision platforming and impalement avoidance more obnoxious than it needed to be. And speaking of obnoxious, why is there no level select for world stages? It's a shame, since Parallel Levels is such a cute idea and has such a great colourful design, though it could have done with its own set of sound effects instead of the Mario ones it appears to be using. If you're patient and have a light touch, it's still a fun and tricky experience, provided you can stave off a rage quit or three.