The game is not as simple as it sounds, breaking convention in many ways. For starters, you cannot move in any direction at will, but only by pointing to the direction you want to go, and then propel yourself forward (with the 'Z' key). Stop the thrust, and you will fall downward to the ocean floor. This means you have to tap the Z key consistently and at the right moments to avoid nasty spikes, strong currents, and other obstacles that can kill you in an instant, not to mention menacing enemies. Speaking of enemies, they are not easy to kill: each type of enemy requires precise timing and good reflexes, as well as astute observation of their movements and weaknesses. Puffer fish, for example, can only be kiled when they are not 'puffed up' with nasty thorns. Discovering the little signs that tell you when enemies are about to become dangerous is part of the fun.

What may turn some people off Ikachan is the relatively high difficulty level, especially at the beginning of the game. But as you gain levels and gets access to more powerful attacks (for example, your pointy head at experience level 2 can destroy porous walls), the game becomes more fun and less frustrating. One nice difference between Ikachan and typical platformers is that there is only one game environment to explore: your underwater surroundings. As you gain new attacks, you can use them to gain access to hitherto inaccessible areas. The game is in Japanese, but you don't really need to read the text to finish this charming and addictive little underdog. Highly recommended! Download to be found in the fansite linked below.