Osmos, smallest idea to be the biggest.
Osmos is a game based on a very small idea. To be big. Nay, the biggest. The game really hits the nail on the head with this feature, even though it's a common mechanic in many flash and small developed games. Instead of levels, upgrades and persistence the reward for your hard work is seeing your masterful orb devour anything in it's way including the oppressors that sought out to destroy you at your weakest form.
With this already addictive aspect of becoming the biggest, Hemisphere games gives you different modes in which you can play. The first is the objective to absorb another marked orb that has it's own artificial intelligence to avoid you as well as become bigger. This mode becomes a fascinating goal since the mechanic to make you go faster is to sacrifice parts of your own orb with the another fundamental law (Newtons Third law, for every action there is an equal and opposite reaction).
As a science geek this facet of the game tickled a very fond physics nerve. Every time you gain orbs you lose velocity since your mass is increasing but the momentum stays the same. It is hard to understand the niches of the game and how wonderful it is with it's sense of physics when you don't already understand the fundamental law that a student does studying physics. If you love mechanical physics, you will enjoy this game primarily because the ideas of Newtons Laws and of Kinematics when studying them are done in very closed and perfect systems. You never see these aspects of Newtons laws come into fruition in real life because there are always underlying variables. In this game, it simulates this perfect world to play with these laws.
The brilliant thing about Osmos is that it can be a play on it's title. At points the game behaves as though your little cells absorbing other little cells. For the first game mode, the idea is that the marked orb is a cell, 'ovarium' or 'biophobe' and so the game feels as though it is biologically based much like the word Osmosis is. However as you progress through the game and you unlock other modes in which you are orbiting large masses, it suddenly becomes a game of the Cosmos. Gravity plays a large part in these game modes with the game's aiding feature of plotting out orbit and letting you know when you're about to be devoured. The game does a great job at blurring the lines between a micro scale (such as the cells) and a macro scale (such as giant planets and galaxy) both at a mechanical and aesthetic level.
Another great facet of this game is it's music. For a game that is described as 'ambient', it's music justifies that description. Hosting a variety of songs from a variety of artists, it suited the game perfectly especially since the game requires a lot of patience.
The paragraphs above are it's most pleasing and fun features of the game. However, playing the game on a very advanced level becomes quickly frustrating and annoying. Since the majority of the game is to become bigger, losing yourself to a larger orb destroys all the work put into becoming as large as you were. Understandably that's part of the game, without that there really is no challenge. However it could've taken measures for less rage-y play. One idea that comes to mind is reversing time to undo mistakes (limited uses of course) so that one mistake doesn't destroy what might have been 20 minutes of building.This could have worked well since the game does already implement manipulation in the time of the game. The game could have used more game play, a change in scenery. But as it is, it is perfectly adequate. As for the design of the game, it is done very well adding new twists to this mechanic. But it's the mechanic that did not resonate too well with me, especially losing all that progress from a simple mistake. It is not entirely the games fault. The one advice I can give to anyone who is thinking about buying the game is asking yourself this. Are you a very patient person? or Can you be patient in the face of constant failure? That is to say if you want to finish the game. More relaxing modes are available and that may be what you are trying to go for, to that I say go ahead