Enter the ambient world of Osmos: elegant, physics-based gameplay, dreamlike visuals, and a minimalist, electronic soundtrack. Your objective is to grow by absorbing other motes. Propel yourself by ejecting matter behind you. But be wise: ejecting matter also shrinks you. Relax… good things come to those who wait. Progress from serenely ambient levels into varied and challenging worlds. Confront attractors, repulsors and intelligent motes with similar abilities and goals as you.
Osmos is the perfect combination of relaxed ambient atmosphere and challenging skill testing puzzles. While it starts of slow, the learning curve ramps up quickly for those hungry for challenge.
The game sports multiple level types, each of which posing a unique challenge and specific goal (such orbiting around a large cellular structure along with thousands of other cells), while keeping the main concept of the game straightforward: devour what is smaller than you, avoid what is larger. Though that truly isn't as easy as it sounds.
The biggest challenge in the game is mastering the core mechanic - the fact that in order to propel yourself forward, you must expel some of your mass behind you. This act not only makes you smaller, but has a chance of feeding the larger red enemies around you and making them even more difficult to surpass in size. This expulsion also allows you to move enemies (sometimes at painfully slow speeds in the more claustrophobic levels), which becomes a very important and tactical aspect of the game quite quickly.
The game itself is beautiful, the music is perfect, and the controls are perfectly suited for the gameplay. The only way to improve the game would be to add some procedurally generated "endless" mode which allows players to relax while playing, as the other game modes all become too difficult to play calmly.