The Game
As you can see, Blue Eater is hungry and must eat blue squares or he will die.
So, the objective on each level is to arrive to the exit and to go next level, before your energy or time goes to zero.
For this, it's usually necessary to eat the blue squares and avoid the red ones.
Dark blue squares have more food than normal blue ones and you can use it twice. Dark red squares cause more damage than normal red ones. Green squares have no effect and can't be eaten (no good taste for Blue Eaters), and black ones are void space, so you can't pass through them.
Anyway, each movement you do causes loss of energy, so think well your movements to save energy.
Before go to the exit you must have the correct key to open it. There are three keys on the level, but only one is the correct. Of course, if you get all three keys on the level, you will open the exit for sure, but then maybe you will not have enough energy left!
One more object is in the level, an Egg. If you get three eggs, you will get the current level password (there is a password for each group of five levels). If you die, you will loose an egg, all the keys and a live.
That's all, so let's go for the blue!