Chrome 42+ disables NPAPI plugins like Unity3d plugin.
Copy and paste the following text into your browser: chrome://flags/#enable-npapi and enable the NPAPI plugin.
Or try another browser like Firefox
Finally there is a remake of the well known Fishy game. Fishy 3D takes place in a beautiful 3D aquarium. Avoid the larger fish as long as possible and eat small fish in order to grow. Use the arrow keys to move.